Fix PM2 logs: echo child output to exec-process stdout/stderr so pm2 monit shows real task output

- exec-process.js: pipe child stdout/stderr to process.stdout/stderr (in addition to RPC appendOutput)
- runtime.js: nodejs/typescript spawn with stdin='ignore' to prevent bun exit on empty pipe

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

Author: lanmower

src/exec-process.js

@@ -38,11 +38,13 @@ async function runChild(child, cleanup) {
   child.stdout?.on('data', async (d) => {
     const str = d.toString('utf8');
     stdout += str;
+    process.stdout.write(str);
     await rpc('appendOutput', { taskId, type: 'stdout', data: str });
   });
   child.stderr?.on('data', async (d) => {
     const str = d.toString('utf8');
     stderr += str;
+    process.stderr.write(str);
     await rpc('appendOutput', { taskId, type: 'stderr', data: str });
   });
   return new Promise((resolve) => {
@@ -83,13 +85,16 @@ async function runCompiled(spawnResult) {
     : { taskId, error: result.stderr || 'Execution failed' });
 }
 
+process.stderr.write('[exec-process] task=' + taskId + ' runtime=' + RUNTIME + ' starting\n');
 const spawnResult = spawnProcess(RUNTIME, code, CWD);
 if (spawnResult.isCompile) {
   await runCompiled(spawnResult);
 } else {
   const result = await runChild(spawnResult.child, spawnResult.cleanup);
+  process.stderr.write('[exec-process] task=' + taskId + ' child exited code=' + result.exitCode + '\n');
   await rpc(result.ok ? 'completeTask' : 'failTask', result.ok
     ? { taskId, result: { success: true, exitCode: result.exitCode, stdout: result.stdout, stderr: result.stderr } }
     : { taskId, error: result.error || result.stderr || 'Execution failed' });
 }
+process.stderr.write('[exec-process] task=' + taskId + ' done\n');
 process.exit(0);

src/runtime.js

@@ -39,16 +39,16 @@ function makeTmp(ext, content) {
   return { dir, file };
 }
 
-function spawnOpts(cwd) {
-  return { cwd: cwd || process.cwd(), stdio: ['pipe', 'pipe', 'pipe'], detached: false };
+function spawnOpts(cwd, stdin = 'pipe') {
+  return { cwd: cwd || process.cwd(), stdio: [stdin, 'pipe', 'pipe'], detached: false };
 }
 
 export function spawnProcess(runtime, code, cwd) {
   let tmpDir = null;
   const cleanup = () => { if (tmpDir) { try { rmSync(tmpDir, { recursive: true, force: true }); } catch {} tmpDir = null; } };
 
   if (runtime === 'nodejs' || runtime === 'typescript') {
-    const child = spawn('bun', ['-e', code], spawnOpts(cwd));
+    const child = spawn('bun', ['-e', code], spawnOpts(cwd, 'ignore'));
     return { child, cleanup };
   }
   if (runtime === 'python') {