feat: harden podman deployment orchestration

backend/src/hermes.ts

@@ -0,0 +1,50 @@
+import { spawn, type ChildProcess } from 'node:child_process';
+import { dirname, join } from 'node:path';
+import { fileURLToPath } from 'node:url';
+
+const here = dirname(fileURLToPath(import.meta.url));
+
+const processMode = process.env.PODMAN_PROCESS ?? 'all';
+type ProcessMode = 'server' | 'agent';
+
+function commandFor(mode: ProcessMode): string[] {
+  return [join(here, `${mode}.js`)];
+}
+
+const modes: ProcessMode[] =
+  processMode === 'server' || processMode === 'agent' ? [processMode] : ['server', 'agent'];
+
+const children: ChildProcess[] = modes.map((mode) =>
+  spawn(process.execPath, commandFor(mode), { stdio: 'inherit' }),
+);
+
+let shuttingDown = false;
+
+function stopAll(signal: NodeJS.Signals = 'SIGTERM') {
+  for (const child of children) {
+    if (!child.killed) child.kill(signal);
+  }
+}
+
+for (const child of children) {
+  child.on('exit', (code, signal) => {
+    if (shuttingDown) return;
+    shuttingDown = true;
+    stopAll();
+    if (signal) {
+      process.kill(process.pid, signal);
+      return;
+    }
+    process.exit(code ?? 1);
+  });
+}
+
+process.on('SIGINT', () => {
+  shuttingDown = true;
+  stopAll('SIGINT');
+});
+
+process.on('SIGTERM', () => {
+  shuttingDown = true;
+  stopAll('SIGTERM');
+});