feat(ECR-017): AskOperations 问答会话只读并 Closed

新增 admin.ask.read、GET /admin/ask/threads*（AskSessionView）与 admin-h5「问答」页；禁改消息/UGC/真支付。

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

apps/api/internal/service/admin/rbac.go

@@ -24,6 +24,7 @@ const (
 	PermMembershipPlansWrite = "admin.membership.plans.write"
 	PermMembershipCodesRead  = "admin.membership.codes.read"
 	PermMembershipCodesWrite = "admin.membership.codes.write"
+	PermAskRead              = "admin.ask.read"
 )
 
 var knownPermissions = map[string]struct{}{
@@ -32,6 +33,7 @@ var knownPermissions = map[string]struct{}{
 	PermContentWrite: {}, PermRolesRead: {}, PermRolesWrite: {},
 	PermUsersStatusWrite: {}, PermMembershipPlansRead: {}, PermMembershipPlansWrite: {},
 	PermMembershipCodesRead: {}, PermMembershipCodesWrite: {},
+	PermAskRead: {},
 }
 
 var (