feat: add gateway auto-start on boot and real health detection

- Auto-detect gateway connectivity on server startup, start gateway if not running
- Fix /health endpoint to actually check gateway reachability instead of just CLI version
- Fix MiniMax CN base_url from /anthropic to /v1
- Frontend connection status now reflects real gateway state

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/stores/app.ts

@@ -17,7 +17,7 @@ export const useAppStore = defineStore('app', () => {
   async function checkConnection() {
     try {
       const res = await checkHealth()
-      connected.value = true
+      connected.value = res.status === 'ok'
       if (res.version) serverVersion.value = res.version
     } catch {
       connected.value = false