feat(codex-link): AITURK work routing setting and beta.40

- Default routing rule (user decision, 15 Oct 2026): repeating/scheduled work goes to the AITURK IDE bot as a cron job; coding stays in Codex (itself or its subagents); 'Codex' or 'sen yap' keeps everything in Codex.
- Settings > Codex Bağlama: choice (recommended / send large work / never / custom text) with a text box and restore-default; written to bridge.json aiturk_hat.
- Bridge re-reads aiturk_hat when bridge.json changes: no restart. IDE apply keeps aiturk_hat instead of wiping it.
- Bridge version 20, IDE 1.0.0-beta.40. Jev untouched.

apps/desktop/electron/codex-link.ts

@@ -286,7 +286,16 @@ export function createCodexLink(deps: CodexLinkDeps): CodexLink {
     }
 
     try {
-      deps.writeTextAtomic(path.join(paths.bridgeHome, 'bridge.json'), serializeCodexBridgeConfig())
+      const bridgeJson = path.join(paths.bridgeHome, 'bridge.json')
+      let previous: null | string = null
+
+      try {
+        previous = deps.readText(bridgeJson)
+      } catch {
+        previous = null
+      }
+
+      deps.writeTextAtomic(bridgeJson, serializeCodexBridgeConfig(previous))
     } catch (error) {
       fail('bridge-config-failed', error)