chore: 基线提交（重构前快照）

重构前保存现有 apps/ 结构基线，供后续各阶段回滚。

Co-Authored-By: Claude <noreply@anthropic.com>

apps/forms/member_level.py

@@ -0,0 +1,10 @@
+from typing import Optional
+
+from pydantic import BaseModel, Field
+
+# 会员等级表单验证
+class MemberLevelForm(BaseModel):
+    id: Optional[int] = Field(None, description="会员等级ID")
+    name: str = Field(..., min_length=1, max_length=255, description="会员等级名称")
+    sort: int = Field(..., ge=0, le=99999, description="会员等级排序")
+