fix: rename ambiguous variable 'l' to 'line' in tests (E741)

Fix 8 flake8 E741 errors in test_title_render_consistency.py
where list comprehension used 'l' as variable name.

tests/unit/test_title_render_consistency.py

@@ -54,7 +54,7 @@ class TestFontSizeCap:
             title_config=config,
         )
         # 解析 Style 行的 Fontsize 字段（第3个字段，索引2）
-        style_line = [l for l in content.splitlines() if l.startswith("Style: TitleStyle")][0]
+        style_line = [line for line in content.splitlines() if line.startswith("Style: TitleStyle")][0]
         fields = [f.strip() for f in style_line.split(",")]
         font_size = int(fields[2])
         assert font_size == 36, f"字号60应被cap到36, 实际={font_size}"
@@ -86,7 +86,7 @@ class TestBooleanStrokeNormalization:
             title_config=config,
         )
         # 解析 Style 行的 Outline 字段（第17个字段，索引16）
-        style_line = [l for l in content.splitlines() if l.startswith("Style: TitleStyle")][0]
+        style_line = [line for line in content.splitlines() if line.startswith("Style: TitleStyle")][0]
         fields = [f.strip() for f in style_line.split(",")]
         outline_width = float(fields[16])
         assert outline_width == 2.0, f"stroke=true 应产生 outline_width=2, 实际={outline_width}"
@@ -101,7 +101,7 @@ class TestBooleanStrokeNormalization:
             title_text="测试标题",
             title_config=config,
         )
-        style_line = [l for l in content.splitlines() if l.startswith("Style: TitleStyle")][0]
+        style_line = [line for line in content.splitlines() if line.startswith("Style: TitleStyle")][0]
         fields = [f.strip() for f in style_line.split(",")]
         outline_width = float(fields[16])
         assert outline_width == 0.0, f"stroke=false 应产生 outline_width=0, 实际={outline_width}"
@@ -116,7 +116,7 @@ class TestBooleanStrokeNormalization:
             title_text="测试标题",
             title_config=config,
         )
-        style_line = [l for l in content.splitlines() if l.startswith("Style: TitleStyle")][0]
+        style_line = [line for line in content.splitlines() if line.startswith("Style: TitleStyle")][0]
         fields = [f.strip() for f in style_line.split(",")]
         outline_width = float(fields[16])
         assert outline_width == 3.0, f"自定义stroke width=3 应保留, 实际={outline_width}"
@@ -135,7 +135,7 @@ class TestBooleanShadowNormalization:
             title_text="测试标题",
             title_config=config,
         )
-        style_line = [l for l in content.splitlines() if l.startswith("Style: TitleStyle")][0]
+        style_line = [line for line in content.splitlines() if line.startswith("Style: TitleStyle")][0]
         fields = [f.strip() for f in style_line.split(",")]
         # Shadow 字段是第18个（索引17）
         shadow_depth = int(fields[17])
@@ -151,7 +151,7 @@ class TestBooleanShadowNormalization:
             title_text="测试标题",
             title_config=config,
         )
-        style_line = [l for l in content.splitlines() if l.startswith("Style: TitleStyle")][0]
+        style_line = [line for line in content.splitlines() if line.startswith("Style: TitleStyle")][0]
         fields = [f.strip() for f in style_line.split(",")]
         shadow_depth = int(fields[17])
         assert shadow_depth == 0, f"shadow=false 应产生 shadow_depth=0, 实际={shadow_depth}"
@@ -166,7 +166,7 @@ class TestBooleanShadowNormalization:
             title_text="测试标题",
             title_config=config,
         )
-        style_line = [l for l in content.splitlines() if l.startswith("Style: TitleStyle")][0]
+        style_line = [line for line in content.splitlines() if line.startswith("Style: TitleStyle")][0]
         fields = [f.strip() for f in style_line.split(",")]
         shadow_depth = int(fields[17])
         assert shadow_depth == 3, f"自定义shadow offset_y=3 应保留, 实际={shadow_depth}"
@@ -198,7 +198,7 @@ class TestFullStyleConsistency:
             title_text="标题文本",
             title_config=config,
         )
-        style_line = [l for l in content.splitlines() if l.startswith("Style: TitleStyle")][0]
+        style_line = [line for line in content.splitlines() if line.startswith("Style: TitleStyle")][0]
         fields = [f.strip() for f in style_line.split(",")]
 
         # Fontname