feat(security): harden gateway boundaries and usage policies

Consolidate subscription usage policy enforcement, privacy-safe persistence, and gateway security hardening into one reviewable change.

Includes bounded HTTP and execution envelopes, header and protocol guards, DNS and relay validation, authentication and secret projection hardening, secure backup/install paths, and regression coverage.

frontend/src/mocks/handler.ts

@@ -5,6 +5,7 @@
 
 import type { AxiosRequestConfig, AxiosResponse } from 'axios'
 import { isDemoMode, DEMO_ACCOUNTS } from '@/config/demo'
+import { log } from '@/utils/logger'
 import {
   MOCK_ADMIN_USER,
   MOCK_NORMAL_USER,
@@ -2322,15 +2323,13 @@ export async function handleMockRequest(config: AxiosRequestConfig): Promise<Axi
       if ((error as Record<string, unknown>)?.response) {
         throw error
       }
-      // eslint-disable-next-line no-console
-      console.error('[Mock] Handler error:', error)
+      log.error('Mock request handler failed', error)
       throw { response: createMockResponse({ detail: '模拟请求处理失败' }, 500) }
     }
   }
 
   // 未匹配的请求返回默认响应
-  // eslint-disable-next-line no-console
-  console.warn(`[Mock] Unhandled request: ${method} ${url}`)
+  log.warn('Mock request was not handled', { method, url })
   return createMockResponse({ message: '演示模式：该接口暂未模拟', demo_mode: true })
 }
 
@@ -4993,7 +4992,7 @@ mockHandlers['GET /api/admin/monitoring/system-status'] = async () => {
       active_streams: 164
     },
     internal_gateway: {
-      status: 'rust_native_control_plane',
+      status: 'disabled',
       path_prefixes: ['/api/', '/v1/', '/v1beta/', '/_gateway/']
     },
     recent_errors: 9