feat(ad-revenue): admin 广告收益报表(按 用户/日期/类型/应用/代码位 聚合)

- 新增 GET /admin/api/ad-revenue-report:展示条数/收益 + 复用金币审计逐条复算做发奖对账
- ad_ecpm/ad_reward/ad_feed_reward 各加 app_env + our_code_id 两列(alembic 迁移)
- ecpm-report / feed-reward 接收并落库 app_env/our_code_id;激励发奖按 ad_session_id 回填
- ad_audit 抽出 audit_rows,报表与逐条审计复用同一复算口径
- 组级 matched 改「组内逐条全一致」,避免应发和==实发和的互相抵消掩盖错误
- list_feedbacks 改 offset 分页并返回 total(配合 admin 页码分页)
- 反馈正文上限 _CONTENT_MAX 2000→200
- 文档:新增 admin-ad-revenue-report,更新 ecpm/feed-reward/feedback 及对应 db docs

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

app/admin/routers/feedback.py

@@ -34,7 +34,7 @@ def list_feedbacks(
     limit: Annotated[int, Query(ge=1, le=100)] = 20,
     cursor: Annotated[int | None, Query()] = None,
 ) -> CursorPage[FeedbackOut]:
-    items, next_cursor = queries.list_feedbacks(
+    items, next_cursor, total = queries.list_feedbacks(
         db,
         status=status,
         user_id=user_id,
@@ -47,7 +47,9 @@ def list_feedbacks(
         cursor=cursor,
     )
     return CursorPage(
-        items=[FeedbackOut.model_validate(f) for f in items], next_cursor=next_cursor,
+        items=[FeedbackOut.model_validate(f) for f in items],
+        next_cursor=next_cursor,
+        total=total,
     )