fix(test): correct confirm API path in test_confirm_generation.py

Route was moved to /api/v1/generation/tasks/{task_id}/confirm but
test file still used /api/v1/tasks/{task_id}/confirm, causing 404.

- Updated app fixture prefix from /api/v1 to /api/v1/generation
- Updated all 9 test URLs to use /api/v1/generation/tasks/ path
- Updated docstring to reflect correct endpoint path

tests/unit/test_confirm_generation.py

@@ -1,6 +1,6 @@
 """确认生成 API 单元测试.
 
-覆盖 POST /tasks/{task_id}/confirm 端点：
+覆盖 POST /generation/tasks/{task_id}/confirm 端点：
   - 预览任务已完成 → 直接复用（mark_confirmed），秒出
   - 预览任务未完成 → 创建新任务走渲染流程
   - 预览任务不存在 → 404
@@ -150,7 +150,7 @@ def app(
     )
 
     test_app = FastAPI()
-    test_app.include_router(router, prefix="/api/v1")
+    test_app.include_router(router, prefix="/api/v1/generation")
 
     def override_get_current_user():
         return FakeAuthenticatedUser()
@@ -228,7 +228,7 @@ class TestConfirmGenerationReuse:
         initial_count = len(gen_task_repo._store)
 
         resp = client.post(
-            f"/api/v1/tasks/{preview.id}/confirm",
+            f"/api/v1/generation/tasks/{preview.id}/confirm",
             json={
                 "output_width": 1080,
                 "output_height": 1920,
@@ -266,7 +266,7 @@ class TestConfirmGenerationReuse:
         gen_task_repo.create(preview)
 
         resp = client.post(
-            f"/api/v1/tasks/{preview.id}/confirm",
+            f"/api/v1/generation/tasks/{preview.id}/confirm",
             json={"cover_url": "https://cdn.example.com/cover.png", "custom_title": "测试标题"},
         )
 
@@ -290,7 +290,7 @@ class TestConfirmGenerationReuse:
 
         with patch("app.api.routes.generation_tasks.safe_enqueue_generation_task", return_value=True):
             resp = client.post(
-                f"/api/v1/tasks/{preview.id}/confirm",
+                f"/api/v1/generation/tasks/{preview.id}/confirm",
                 json={"output_width": 1080, "output_height": 1920},
             )
 
@@ -308,7 +308,7 @@ class TestConfirmGenerationErrors:
     def test_confirm_not_found(self, client: TestClient) -> None:
         """预览任务不存在 → 404"""
         resp = client.post(
-            "/api/v1/tasks/nonexistent-task/confirm",
+            "/api/v1/generation/tasks/nonexistent-task/confirm",
             json={"output_width": 1080, "output_height": 1920},
         )
         assert resp.status_code == 404
@@ -324,7 +324,7 @@ class TestConfirmGenerationErrors:
         gen_task_repo.create(preview)
 
         resp = client.post(
-            f"/api/v1/tasks/{preview.id}/confirm",
+            f"/api/v1/generation/tasks/{preview.id}/confirm",
             json={"output_width": 1080, "output_height": 1920},
         )
         assert resp.status_code == 403
@@ -345,7 +345,7 @@ class TestConfirmGenerationErrors:
         gen_task_repo.create(preview)
 
         resp = client.post(
-            f"/api/v1/tasks/{preview.id}/confirm",
+            f"/api/v1/generation/tasks/{preview.id}/confirm",
             json={"output_width": 1920, "output_height": 1080},
         )
 
@@ -373,7 +373,7 @@ class TestConfirmGenerationErrors:
         gen_task_repo.create(preview)
 
         resp = client.post(
-            f"/api/v1/tasks/{preview.id}/confirm",
+            f"/api/v1/generation/tasks/{preview.id}/confirm",
             json={
                 "output_width": 1080,
                 "output_height": 1920,
@@ -397,7 +397,7 @@ class TestConfirmGenerationErrors:
         gen_task_repo.create(preview)
 
         resp = client.post(
-            f"/api/v1/tasks/{preview.id}/confirm",
+            f"/api/v1/generation/tasks/{preview.id}/confirm",
             json={},
         )
 
@@ -419,7 +419,7 @@ class TestConfirmGenerationErrors:
 
         with patch("app.api.routes.generation_tasks.safe_enqueue_generation_task", return_value=True):
             resp = client.post(
-                f"/api/v1/tasks/{preview.id}/confirm",
+                f"/api/v1/generation/tasks/{preview.id}/confirm",
                 json={"output_width": 720, "output_height": 1280},
             )