feat(ECR-020): QualityFeedback 问答质量反馈并 Closed

新增 ask_quality_feedback、运营/C端评分 API 与 admin-h5 问答反馈区；禁改消息/UGC/真支付。

Co-authored-by: Cursor <cursoragent@cursor.com>

docs/CONTRACT_DIFF/ECR-020.yaml

@@ -0,0 +1,26 @@
+ecr: ECR-020
+capability: AskOperations
+bounded_context: Ask_Ops
+parent: WAVE0-FROZEN
+predecessor: ECR-019
+change:
+  type: additive
+breaking_change: false
+migration_required: true
+compatibility_notes: >
+  Adds ask_quality_feedback and admin/user feedback APIs.
+  No message body mutation.
+
+apis:
+  - method: GET
+    path: /api/v1/admin/ask/feedback
+    change: added
+  - method: POST
+    path: /api/v1/admin/ask/threads/{id}/feedback
+    change: added
+  - method: POST
+    path: /api/v1/ask/threads/{id}/feedback
+    change: added
+perms:
+  - code: admin.ask.feedback.write
+    change: added