fix(mindspace): edit_file 落盘、Finish 聊天 merge 与回归守卫

- finish-sync 支持 edit_file 覆盖 public HTML
- Finish 同步 merge 本地流式消息，剥离 agent 内部前缀
- 新增 verify:mindspace-publish-guards 与 AGENTS.md 跨工具说明
- 发版脚本接入回归门禁；103 runtime 发布含备份回退

Co-authored-by: Cursor <cursoragent@cursor.com>

scripts/verify-mindspace-publish-guards.mjs

@@ -0,0 +1,35 @@
+import { spawnSync } from 'node:child_process';
+import path from 'node:path';
+
+const root = path.resolve(new URL('..', import.meta.url).pathname);
+const withRuntime =
+  process.argv.includes('--with-runtime') || process.env.MINDSPACE_VERIFY_RUNTIME === '1';
+
+function run(label, args) {
+  const result = spawnSync(process.execPath, args, {
+    cwd: root,
+    stdio: 'inherit',
+  });
+  if (result.status !== 0) {
+    throw new Error(`${label} failed with exit code ${result.status ?? 'unknown'}`);
+  }
+}
+
+run('MindSpace publish + chat finish unit tests', [
+  '--test',
+  'mindspace-public-finish-sync.test.mjs',
+  'conversation-display.test.mjs',
+  'chat-finish-sync.test.mjs',
+]);
+
+run('chat finish sync source guards', ['scripts/verify-chat-finish-sync.mjs']);
+
+if (withRuntime) {
+  run('public finish sync runtime guard', ['scripts/verify-public-finish-sync-runtime.mjs']);
+}
+
+console.log(
+  withRuntime
+    ? 'mindspace publish + chat finish regression guards ok (with runtime)'
+    : 'mindspace publish + chat finish regression guards ok',
+);