feat(ECR-021): AICoreConfig SystemPrompt 只读并 Closed

新增 system_prompts 目录、admin.ai_config.read 与 admin-h5「AI」页；本切片不改运行时 Prompt、禁写发布/UGC/真支付。

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

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

@@ -27,6 +27,7 @@ const (
 	PermAskRead              = "admin.ask.read"
 	PermAskFeedbackWrite     = "admin.ask.feedback.write"
 	PermContentSafetyRead    = "admin.content_safety.read"
+	PermAIConfigRead         = "admin.ai_config.read"
 )
 
 var knownPermissions = map[string]struct{}{
@@ -36,6 +37,7 @@ var knownPermissions = map[string]struct{}{
 	PermUsersStatusWrite: {}, PermMembershipPlansRead: {}, PermMembershipPlansWrite: {},
 	PermMembershipCodesRead: {}, PermMembershipCodesWrite: {},
 	PermAskRead: {}, PermAskFeedbackWrite: {}, PermContentSafetyRead: {},
+	PermAIConfigRead: {},
 }
 
 var (