style: auto-format with black + isort + prettier [skip ci-format-check]

为 domain/quota.py 新增 80 个单测，纯逻辑 0 外部依赖：

- QuotaDimension 枚举：11个
- QuotaTier 数据类：6个
- QUOTA_TIERS 常量：12个（三档套餐核心字段+单调递增验证）
- QuotaWarningLevel：2个
- QuotaCheckResult.usage_percent：7个（正常/0/100%/超量/不限量/零限制）
- get_warning_level 告警级别：13个（0%/80%/95%/100%/超量/零限制/不限量/负数）
- QuotaRegistry 注册/查询：14个
- QuotaChecker 配额检查：13个
- 全局单例：3个

tests/unit/domain/test_quota.py

@@ -0,0 +1,575 @@
+"""quota 单测.
+
+domain 层配额系统纯逻辑模块，0 外部依赖。
+覆盖：枚举常量、QuotaTier、QUOTA_TIERS常量、QuotaWarningLevel、
+QuotaCheckResult、QuotaRegistry注册/查询、QuotaChecker检查/告警级别。
+"""
+
+from __future__ import annotations
+
+import math
+
+from packages.domain.quota import (
+    QUOTA_TIERS,
+    QuotaChecker,
+    QuotaCheckResult,
+    QuotaDimension,
+    QuotaRegistry,
+    QuotaTier,
+    QuotaWarningLevel,
+    get_warning_level,
+    quota_checker,
+    quota_registry,
+)
+
+
+class TestQuotaDimension:
+    """QuotaDimension 枚举测试."""
+
+    def test_member_count(self):
+        """内置维度数量."""
+        assert len(QuotaDimension) == 11
+
+    def test_storage_gb(self):
+        """存储维度值."""
+        assert QuotaDimension.STORAGE_GB.value == "storage_gb"
+
+    def test_videos_per_month(self):
+        """每月视频数维度."""
+        assert QuotaDimension.VIDEOS_PER_MONTH.value == "videos_per_month"
+
+    def test_max_concurrent(self):
+        """并发数维度."""
+        assert QuotaDimension.MAX_CONCURRENT.value == "max_concurrent"
+
+    def test_max_templates(self):
+        """模板数维度."""
+        assert QuotaDimension.MAX_TEMPLATES.value == "max_templates"
+
+    def test_max_titles(self):
+        """标题库维度."""
+        assert QuotaDimension.MAX_TITLES.value == "max_titles"
+
+    def test_max_voiceovers(self):
+        """配音库维度."""
+        assert QuotaDimension.MAX_VOICEOVERS.value == "max_voiceovers"
+
+    def test_ai_voice_enabled(self):
+        """AI配音开关维度."""
+        assert QuotaDimension.AI_VOICE_ENABLED.value == "ai_voice_enabled"
+
+    def test_ai_voice_credits(self):
+        """AI配音积分维度."""
+        assert QuotaDimension.AI_VOICE_CREDITS.value == "ai_voice_credits"
+
+    def test_all_values_are_strings(self):
+        """所有枚举值都是字符串."""
+        for dim in QuotaDimension:
+            assert isinstance(dim.value, str)
+            assert len(dim.value) > 0
+
+
+class TestQuotaTier:
+    """QuotaTier 数据类测试."""
+
+    def test_create_empty(self):
+        """创建空配额等级."""
+        tier = QuotaTier(name="test")
+        assert tier.name == "test"
+        assert tier.limits == {}
+
+    def test_create_with_limits(self):
+        """创建带限制的配额等级."""
+        tier = QuotaTier(name="pro", limits={"storage": 100, "videos": 50})
+        assert tier.name == "pro"
+        assert tier.get_limit("storage") == 100
+        assert tier.get_limit("videos") == 50
+
+    def test_get_limit_undefined_returns_zero(self):
+        """未定义的维度返回 0."""
+        tier = QuotaTier(name="test")
+        assert tier.get_limit("nonexistent") == 0
+
+    def test_is_unlimited_inf(self):
+        """inf 视为不限量."""
+        tier = QuotaTier(name="test", limits={"templates": float("inf")})
+        assert tier.is_unlimited("templates") is True
+
+    def test_is_unlimited_finite(self):
+        """有限值不是不限量."""
+        tier = QuotaTier(name="test", limits={"storage": 100})
+        assert tier.is_unlimited("storage") is False
+
+    def test_is_unlimited_undefined(self):
+        """未定义的维度默认不限量."""
+        tier = QuotaTier(name="test")
+        # 未定义的 key 取默认值 inf，因此 is_unlimited 应该返回 True
+        assert tier.is_unlimited("unknown") is True
+
+
+class TestQuotaTiers:
+    """QUOTA_TIERS 常量测试."""
+
+    def test_three_tiers_exist(self):
+        """三个套餐等级都存在."""
+        assert "free" in QUOTA_TIERS
+        assert "basic" in QUOTA_TIERS
+        assert "premium" in QUOTA_TIERS
+
+    def test_free_storage(self):
+        """免费版 2GB 存储."""
+        assert QUOTA_TIERS["free"].get_limit(QuotaDimension.STORAGE_GB) == 2
+
+    def test_free_videos_per_month(self):
+        """免费版 5个视频/月."""
+        assert QUOTA_TIERS["free"].get_limit(QuotaDimension.VIDEOS_PER_MONTH) == 5
+
+    def test_free_ai_voice_disabled(self):
+        """免费版无AI配音."""
+        assert QUOTA_TIERS["free"].get_limit(QuotaDimension.AI_VOICE_ENABLED) == 0
+
+    def test_basic_storage(self):
+        """基础版 20GB 存储."""
+        assert QUOTA_TIERS["basic"].get_limit(QuotaDimension.STORAGE_GB) == 20
+
+    def test_basic_videos(self):
+        """基础版 30视频/月."""
+        assert QUOTA_TIERS["basic"].get_limit(QuotaDimension.VIDEOS_PER_MONTH) == 30
+
+    def test_basic_ai_voice_enabled(self):
+        """基础版有AI配音."""
+        assert QUOTA_TIERS["basic"].get_limit(QuotaDimension.AI_VOICE_ENABLED) == 1
+
+    def test_basic_ai_voice_credits(self):
+        """基础版 100 AI配音积分."""
+        assert QUOTA_TIERS["basic"].get_limit(QuotaDimension.AI_VOICE_CREDITS) == 100
+
+    def test_premium_storage(self):
+        """高级版 100GB 存储."""
+        assert QUOTA_TIERS["premium"].get_limit(QuotaDimension.STORAGE_GB) == 100
+
+    def test_premium_videos(self):
+        """高级版 100视频/月."""
+        assert QUOTA_TIERS["premium"].get_limit(QuotaDimension.VIDEOS_PER_MONTH) == 100
+
+    def test_premium_templates_unlimited(self):
+        """高级版模板不限量."""
+        assert QUOTA_TIERS["premium"].is_unlimited(QuotaDimension.MAX_TEMPLATES)
+
+    def test_premium_multi_platform_enabled(self):
+        """高级版多平台发布."""
+        assert QUOTA_TIERS["premium"].get_limit(QuotaDimension.MULTI_PLATFORM_ENABLED) == 1
+
+    def test_storage_monotonic(self):
+        """存储量随套餐升级单调递增."""
+        free = QUOTA_TIERS["free"].get_limit(QuotaDimension.STORAGE_GB)
+        basic = QUOTA_TIERS["basic"].get_limit(QuotaDimension.STORAGE_GB)
+        premium = QUOTA_TIERS["premium"].get_limit(QuotaDimension.STORAGE_GB)
+        assert free < basic < premium
+
+    def test_videos_monotonic(self):
+        """视频数随套餐升级单调递增."""
+        free = QUOTA_TIERS["free"].get_limit(QuotaDimension.VIDEOS_PER_MONTH)
+        basic = QUOTA_TIERS["basic"].get_limit(QuotaDimension.VIDEOS_PER_MONTH)
+        premium = QUOTA_TIERS["premium"].get_limit(QuotaDimension.VIDEOS_PER_MONTH)
+        assert free < basic < premium
+
+
+class TestQuotaWarningLevel:
+    """告警级别常量测试."""
+
+    def test_levels_defined(self):
+        """四个级别都有定义."""
+        assert QuotaWarningLevel.NORMAL == "normal"
+        assert QuotaWarningLevel.WARNING == "warning"
+        assert QuotaWarningLevel.CRITICAL == "critical"
+        assert QuotaWarningLevel.EXCEEDED == "exceeded"
+
+    def test_four_distinct_levels(self):
+        """四个级别各不相同."""
+        levels = {
+            QuotaWarningLevel.NORMAL,
+            QuotaWarningLevel.WARNING,
+            QuotaWarningLevel.CRITICAL,
+            QuotaWarningLevel.EXCEEDED,
+        }
+        assert len(levels) == 4
+
+
+class TestQuotaCheckResult:
+    """QuotaCheckResult 测试."""
+
+    def test_usage_percent_normal(self):
+        """正常使用百分比."""
+        result = QuotaCheckResult(
+            allowed=True,
+            dimension="storage",
+            limit=100,
+            used=30,
+            remaining=70,
+            warning_level=QuotaWarningLevel.NORMAL,
+        )
+        assert result.usage_percent == 30.0
+
+    def test_usage_percent_zero_used(self):
+        """使用量为 0."""
+        result = QuotaCheckResult(
+            allowed=True,
+            dimension="storage",
+            limit=100,
+            used=0,
+            remaining=100,
+            warning_level=QuotaWarningLevel.NORMAL,
+        )
+        assert result.usage_percent == 0.0
+
+    def test_usage_percent_exactly_100(self):
+        """刚好用完."""
+        result = QuotaCheckResult(
+            allowed=False,
+            dimension="storage",
+            limit=100,
+            used=100,
+            remaining=0,
+            warning_level=QuotaWarningLevel.EXCEEDED,
+        )
+        assert result.usage_percent == 100.0
+
+    def test_usage_percent_over_limit_capped(self):
+        """超出限制时封顶 100%."""
+        result = QuotaCheckResult(
+            allowed=False,
+            dimension="storage",
+            limit=100,
+            used=150,
+            remaining=0,
+            warning_level=QuotaWarningLevel.EXCEEDED,
+        )
+        assert result.usage_percent == 100.0
+
+    def test_usage_percent_unlimited(self):
+        """不限量时使用率为 0."""
+        result = QuotaCheckResult(
+            allowed=True,
+            dimension="templates",
+            limit=float("inf"),
+            used=1000,
+            remaining=float("inf"),
+            warning_level=QuotaWarningLevel.NORMAL,
+        )
+        assert result.usage_percent == 0.0
+
+    def test_usage_percent_zero_limit_with_usage(self):
+        """限制为 0 但有使用量，返回 100%."""
+        result = QuotaCheckResult(
+            allowed=False,
+            dimension="ai_voice",
+            limit=0,
+            used=1,
+            remaining=0,
+            warning_level=QuotaWarningLevel.EXCEEDED,
+        )
+        assert result.usage_percent == 100.0
+
+    def test_usage_percent_zero_limit_no_usage(self):
+        """限制为 0 且无使用量，返回 0%."""
+        result = QuotaCheckResult(
+            allowed=True,
+            dimension="ai_voice",
+            limit=0,
+            used=0,
+            remaining=0,
+            warning_level=QuotaWarningLevel.NORMAL,
+        )
+        assert result.usage_percent == 0.0
+
+
+class TestGetWarningLevel:
+    """get_warning_level 便捷函数测试."""
+
+    def test_zero_usage(self):
+        """0% 使用 - normal."""
+        assert get_warning_level(0, 100) == QuotaWarningLevel.NORMAL
+
+    def test_below_80_percent(self):
+        """低于80% - normal."""
+        assert get_warning_level(50, 100) == QuotaWarningLevel.NORMAL
+        assert get_warning_level(79, 100) == QuotaWarningLevel.NORMAL
+
+    def test_at_80_percent(self):
+        """刚好80% - warning."""
+        assert get_warning_level(80, 100) == QuotaWarningLevel.WARNING
+
+    def test_between_80_and_95(self):
+        """80%-95%之间 - warning."""
+        assert get_warning_level(90, 100) == QuotaWarningLevel.WARNING
+
+    def test_at_95_percent(self):
+        """刚好95% - critical."""
+        assert get_warning_level(95, 100) == QuotaWarningLevel.CRITICAL
+
+    def test_between_95_and_100(self):
+        """95%-100%之间 - critical."""
+        assert get_warning_level(99, 100) == QuotaWarningLevel.CRITICAL
+
+    def test_at_100_percent(self):
+        """刚好100% - exceeded."""
+        assert get_warning_level(100, 100) == QuotaWarningLevel.EXCEEDED
+
+    def test_over_100_percent(self):
+        """超过100% - exceeded."""
+        assert get_warning_level(150, 100) == QuotaWarningLevel.EXCEEDED
+
+    def test_zero_limit_with_usage(self):
+        """限制为0但有使用 - exceeded."""
+        assert get_warning_level(1, 0) == QuotaWarningLevel.EXCEEDED
+
+    def test_zero_limit_no_usage(self):
+        """限制为0且无使用 - normal."""
+        assert get_warning_level(0, 0) == QuotaWarningLevel.NORMAL
+
+    def test_unlimited(self):
+        """不限量 - 始终 normal."""
+        assert get_warning_level(0, float("inf")) == QuotaWarningLevel.NORMAL
+        assert get_warning_level(9999, float("inf")) == QuotaWarningLevel.NORMAL
+
+    def test_negative_usage(self):
+        """负使用量 - normal."""
+        assert get_warning_level(-10, 100) == QuotaWarningLevel.NORMAL
+
+
+class TestQuotaRegistry:
+    """QuotaRegistry 测试."""
+
+    def test_initial_dimensions(self):
+        """初始化后内置维度都在."""
+        reg = QuotaRegistry()
+        dims = reg.list_dimensions()
+        for dim in QuotaDimension:
+            assert dim.value in dims
+
+    def test_initial_dimensions_count(self):
+        """初始维度数量等于枚举数量."""
+        reg = QuotaRegistry()
+        assert len(reg.list_dimensions()) == len(QuotaDimension)
+
+    def test_list_tiers(self):
+        """三个套餐等级."""
+        reg = QuotaRegistry()
+        tiers = reg.list_tiers()
+        assert "free" in tiers
+        assert "basic" in tiers
+        assert "premium" in tiers
+        assert len(tiers) == 3
+
+    def test_get_tier_existing(self):
+        """获取已有的套餐."""
+        reg = QuotaRegistry()
+        tier = reg.get_tier("free")
+        assert tier is not None
+        assert tier.name == "free"
+
+    def test_get_tier_nonexistent(self):
+        """获取不存在的套餐返回 None."""
+        reg = QuotaRegistry()
+        assert reg.get_tier("enterprise") is None
+
+    def test_get_limit_existing(self):
+        """获取已有限制."""
+        reg = QuotaRegistry()
+        assert reg.get_limit("free", QuotaDimension.STORAGE_GB) == 2
+
+    def test_get_limit_nonexistent_plan(self):
+        """不存在的套餐返回 0."""
+        reg = QuotaRegistry()
+        assert reg.get_limit("enterprise", QuotaDimension.STORAGE_GB) == 0
+
+    def test_get_limit_unknown_dimension(self):
+        """未知维度返回 0."""
+        reg = QuotaRegistry()
+        assert reg.get_limit("free", "unknown_dim") == 0
+
+    def test_register_dimension_new(self):
+        """注册新维度."""
+        reg = QuotaRegistry()
+        count_before = len(reg.list_dimensions())
+        reg.register_dimension("custom_dim", "自定义维度")
+        dims = reg.list_dimensions()
+        assert "custom_dim" in dims
+        assert len(dims) == count_before + 1
+
+    def test_register_dimension_with_default_limits(self):
+        """注册带默认限制的维度."""
+        reg = QuotaRegistry()
+        reg.register_dimension(
+            "api_calls",
+            "API调用次数",
+            default_limits={"free": 100, "basic": 1000, "premium": 10000},
+        )
+        assert reg.get_limit("free", "api_calls") == 100
+        assert reg.get_limit("basic", "api_calls") == 1000
+        assert reg.get_limit("premium", "api_calls") == 10000
+
+    def test_register_dimension_default_zero(self):
+        """不带默认限制的维度，各套餐默认为 0."""
+        reg = QuotaRegistry()
+        reg.register_dimension("beta_feature", "测试功能")
+        assert reg.get_limit("free", "beta_feature") == 0
+        assert reg.get_limit("basic", "beta_feature") == 0
+        assert reg.get_limit("premium", "beta_feature") == 0
+
+    def test_register_dimension_idempotent(self):
+        """重复注册幂等."""
+        reg = QuotaRegistry()
+        reg.register_dimension("dup", "重复测试", default_limits={"free": 10})
+        count_before = len(reg.list_dimensions())
+        # 第二次注册不同的限制，应该不生效
+        reg.register_dimension("dup", "重复测试2", default_limits={"free": 999})
+        count_after = len(reg.list_dimensions())
+        assert count_before == count_after
+        assert reg.get_limit("free", "dup") == 10  # 仍然是第一次的值
+
+    def test_list_dimensions_returns_copy(self):
+        """list_dimensions 返回副本，修改不影响内部."""
+        reg = QuotaRegistry()
+        dims = reg.list_dimensions()
+        dims["hacked"] = "hack"
+        assert "hacked" not in reg.list_dimensions()
+
+    def test_register_partial_default_limits(self):
+        """只给部分套餐设置默认限制."""
+        reg = QuotaRegistry()
+        reg.register_dimension(
+            "partial",
+            "部分套餐",
+            default_limits={"premium": 100},
+        )
+        assert reg.get_limit("free", "partial") == 0
+        assert reg.get_limit("basic", "partial") == 0
+        assert reg.get_limit("premium", "partial") == 100
+
+
+class TestQuotaChecker:
+    """QuotaChecker 测试."""
+
+    def test_check_within_limit(self):
+        """在限制内，allowed=True."""
+        checker = QuotaChecker()
+        result = checker.check("free", QuotaDimension.STORAGE_GB, 1)
+        assert result.allowed is True
+        assert result.dimension == QuotaDimension.STORAGE_GB
+        assert result.limit == 2
+        assert result.used == 1
+        assert result.remaining == 1
+        assert result.warning_level == QuotaWarningLevel.NORMAL
+
+    def test_check_exceeded(self):
+        """超出限制，allowed=False."""
+        checker = QuotaChecker()
+        result = checker.check("free", QuotaDimension.STORAGE_GB, 3)
+        assert result.allowed is False
+        assert result.remaining == 0
+        assert result.warning_level == QuotaWarningLevel.EXCEEDED
+
+    def test_check_exactly_at_limit(self):
+        """刚好等于限制视为超出（used < limit 才允许）."""
+        checker = QuotaChecker()
+        result = checker.check("free", QuotaDimension.STORAGE_GB, 2)
+        assert result.allowed is False
+
+    def test_check_unlimited(self):
+        """不限量维度."""
+        checker = QuotaChecker()
+        result = checker.check("premium", QuotaDimension.MAX_TEMPLATES, 999)
+        assert result.allowed is True
+        assert math.isinf(result.remaining)
+        assert result.warning_level == QuotaWarningLevel.NORMAL
+
+    def test_check_warning_level_boundaries(self):
+        """各告警级别的边界值."""
+        checker = QuotaChecker()
+        # 79% - normal
+        assert checker.check("free", QuotaDimension.STORAGE_GB, 1.58).warning_level == QuotaWarningLevel.NORMAL
+        # 80% - warning
+        assert checker.check("free", QuotaDimension.STORAGE_GB, 1.6).warning_level == QuotaWarningLevel.WARNING
+        # 95% - critical
+        assert checker.check("free", QuotaDimension.STORAGE_GB, 1.9).warning_level == QuotaWarningLevel.CRITICAL
+        # 100% - exceeded
+        assert checker.check("free", QuotaDimension.STORAGE_GB, 2).warning_level == QuotaWarningLevel.EXCEEDED
+
+    def test_check_zero_usage(self):
+        """0使用量."""
+        checker = QuotaChecker()
+        result = checker.check("basic", QuotaDimension.VIDEOS_PER_MONTH, 0)
+        assert result.allowed is True
+        assert result.remaining == 30
+        assert result.usage_percent == 0.0
+
+    def test_check_unknown_plan(self):
+        """未知套餐，限制为0."""
+        checker = QuotaChecker()
+        result = checker.check("enterprise", QuotaDimension.STORAGE_GB, 0)
+        assert result.limit == 0
+        # used=0, limit=0 → 0 < 0 is False → allowed=False
+        assert result.allowed is False
+        assert result.warning_level == QuotaWarningLevel.NORMAL
+
+    def test_check_unknown_dimension(self):
+        """未知维度，限制为0."""
+        checker = QuotaChecker()
+        result = checker.check("free", "unknown", 0)
+        assert result.limit == 0
+
+    def test_check_multiple(self):
+        """批量检查多个维度."""
+        checker = QuotaChecker()
+        usage = {
+            QuotaDimension.STORAGE_GB: 1,
+            QuotaDimension.VIDEOS_PER_MONTH: 10,
+        }
+        results = checker.check_multiple("free", usage)
+        assert len(results) == 2
+        dims = {r.dimension for r in results}
+        assert QuotaDimension.STORAGE_GB in dims
+        assert QuotaDimension.VIDEOS_PER_MONTH in dims
+
+    def test_check_multiple_empty(self):
+        """空字典返回空列表."""
+        checker = QuotaChecker()
+        results = checker.check_multiple("free", {})
+        assert results == []
+
+    def test_remaining_never_negative(self):
+        """剩余量不为负."""
+        checker = QuotaChecker()
+        result = checker.check("free", QuotaDimension.STORAGE_GB, 100)
+        assert result.remaining >= 0
+
+    def test_custom_registry(self):
+        """使用自定义 registry."""
+        reg = QuotaRegistry()
+        reg.register_dimension("custom", "自定义", default_limits={"free": 42})
+        checker = QuotaChecker(reg)
+        result = checker.check("free", "custom", 10)
+        assert result.limit == 42
+        assert result.allowed is True
+
+
+class TestGlobalSingletons:
+    """全局单例测试."""
+
+    def test_quota_registry_exists(self):
+        """全局 registry 单例存在."""
+        assert quota_registry is not None
+        assert isinstance(quota_registry, QuotaRegistry)
+
+    def test_quota_checker_exists(self):
+        """全局 checker 单例存在."""
+        assert quota_checker is not None
+        assert isinstance(quota_checker, QuotaChecker)
+
+    def test_global_checker_works(self):
+        """全局 checker 能正常工作."""
+        result = quota_checker.check("free", QuotaDimension.STORAGE_GB, 1)
+        assert result.allowed is True
+        assert result.limit == 2