fix(proxy): stabilize live takeover and provider editing

- Skip live writes when takeover is active and proxy is running
- Refresh live backups from provider edits during takeover
- Sync live tokens to DB without clobbering real keys with placeholders
- Avoid injecting extra placeholder keys into Claude live env
- Reapply takeover after proxy listen address/port changes
- In takeover mode, edit dialog uses DB config and keeps API key state in sync

src/App.tsx

@@ -578,6 +578,7 @@ function App() {
         }}
         onSubmit={handleEditProvider}
         appId={activeApp}
+        isProxyTakeover={isProxyRunning && isTakeoverActive}
       />
 
       {usageProvider && (