refactor: consolidate runtime helpers

src/group-queue-ipc.ts

@@ -0,0 +1,21 @@
+import fs from 'fs';
+import path from 'path';
+
+import { DATA_DIR } from './config.js';
+
+export function queueFollowUpMessage(groupFolder: string, text: string): string {
+  const inputDir = path.join(DATA_DIR, 'ipc', groupFolder, 'input');
+  fs.mkdirSync(inputDir, { recursive: true });
+  const filename = `${Date.now()}-${Math.random().toString(36).slice(2, 6)}.json`;
+  const filepath = path.join(inputDir, filename);
+  const tempPath = `${filepath}.tmp`;
+  fs.writeFileSync(tempPath, JSON.stringify({ type: 'message', text }));
+  fs.renameSync(tempPath, filepath);
+  return filename;
+}
+
+export function writeCloseSentinel(groupFolder: string): void {
+  const inputDir = path.join(DATA_DIR, 'ipc', groupFolder, 'input');
+  fs.mkdirSync(inputDir, { recursive: true });
+  fs.writeFileSync(path.join(inputDir, '_close'), '');
+}