Fix Codex title MCP startup and remote terminal spawning

cli/src/codex/utils/buildHapiMcpBridge.ts

@@ -7,6 +7,7 @@
 
 import { startHappyServer } from '@/claude/utils/startHappyServer';
 import { getHappyCliCommand } from '@/utils/spawnHappyCLI';
+import { spawnSync } from 'node:child_process';
 import type { ApiSessionClient } from '@/api/apiSession';
 
 /**
@@ -39,6 +40,61 @@ export interface HapiMcpBridgeOptions {
     emitTitleSummary?: boolean;
 }
 
+// Codex app-server 0.130 can close a Bun-backed MCP stdio server while
+// processing the initialize response. Keep a tiny Node stdio shim in front of
+// the real hapi MCP bridge so Codex talks to a stable Node process. This is
+// intentionally inline instead of a sidecar file so compiled/release HAPI can
+// spawn it without needing extra packaged assets.
+const HAPI_MCP_STDIO_PROXY_SCRIPT = String.raw`
+const { spawn } = require('node:child_process');
+const [command, ...args] = process.argv.slice(1);
+if (!command) {
+  process.stderr.write('[hapi-mcp-proxy] Missing child command\n');
+  process.exit(2);
+}
+const child = spawn(command, args, {
+  stdio: ['pipe', 'pipe', 'pipe'],
+  env: process.env,
+  windowsHide: process.platform === 'win32'
+});
+let exiting = false;
+function safeEnd(stream) { try { stream.end(); } catch {} }
+function safeKill() {
+  if (child.killed || child.exitCode !== null) return;
+  try { child.kill(); } catch {}
+}
+process.stdin.on('data', (chunk) => {
+  if (!child.stdin.destroyed) child.stdin.write(chunk);
+});
+process.stdin.on('end', () => safeEnd(child.stdin));
+process.stdin.on('error', () => safeEnd(child.stdin));
+child.stdout.on('data', (chunk) => process.stdout.write(chunk));
+child.stderr.on('data', (chunk) => process.stderr.write(chunk));
+child.on('error', (error) => {
+  process.stderr.write('[hapi-mcp-proxy] Failed to start child: ' + (error instanceof Error ? error.message : String(error)) + '\n');
+  if (!exiting) { exiting = true; process.exit(1); }
+});
+child.on('exit', (code, signal) => {
+  if (exiting) return;
+  exiting = true;
+  if (signal) { process.kill(process.pid, signal); return; }
+  process.exit(code ?? 0);
+});
+process.on('SIGTERM', () => { safeKill(); process.exit(143); });
+process.on('SIGINT', () => { safeKill(); process.exit(130); });
+process.on('exit', safeKill);
+`;
+
+function resolveNodeExecutable(): string | null {
+    const override = process.env.HAPI_NODE_EXECUTABLE?.trim();
+    if (override) {
+        return override;
+    }
+
+    const result = spawnSync('node', ['--version'], { stdio: 'ignore' });
+    return result.status === 0 ? 'node' : null;
+}
+
 /**
  * Start the hapi MCP bridge server and return the configuration
  * needed to connect Codex to it.
@@ -54,17 +110,21 @@ export async function buildHapiMcpBridge(
         emitTitleSummary: options.emitTitleSummary
     });
     const bridgeCommand = getHappyCliCommand(['mcp', '--url', happyServer.url]);
+    const nodeCommand = resolveNodeExecutable();
+    const hapiMcpServer = nodeCommand
+        ? {
+            command: nodeCommand,
+            args: ['-e', HAPI_MCP_STDIO_PROXY_SCRIPT, bridgeCommand.command, ...bridgeCommand.args]
+        }
+        : bridgeCommand;
 
     return {
         server: {
             url: happyServer.url,
             stop: happyServer.stop
         },
         mcpServers: {
-            hapi: {
-                command: bridgeCommand.command,
-                args: bridgeCommand.args
-            }
+            hapi: hapiMcpServer
         }
     };
 }