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>

chat-finish-sync.test.mjs

@@ -0,0 +1,54 @@
+import test from 'node:test';
+import assert from 'node:assert/strict';
+
+import {
+  mergeConversationSnapshot,
+  mergeSessionMessagesAfterFinish,
+} from './chat-finish-sync.mjs';
+
+const msg = (id, role, text) => ({
+  id,
+  role,
+  metadata: { userVisible: true },
+  content: [{ type: 'text', text }],
+});
+
+test('mergeConversationSnapshot keeps local-only messages when server snapshot is shorter', () => {
+  const local = [
+    msg('u1', 'user', '生成一个页面'),
+    msg('a1', 'assistant', '正在写入 public/demo.html…'),
+    msg('a2', 'assistant', '页面已生成'),
+  ];
+  const server = [msg('u1', 'user', '生成一个页面')];
+  const merged = mergeConversationSnapshot(local, server);
+  assert.equal(merged.length, 3);
+  assert.deepEqual(
+    merged.map((message) => message.id),
+    ['u1', 'a1', 'a2'],
+  );
+});
+
+test('mergeConversationSnapshot prefers server content for shared message ids', () => {
+  const local = [msg('u1', 'user', '旧文案')];
+  const server = [msg('u1', 'user', '新文案')];
+  const merged = mergeConversationSnapshot(local, server);
+  assert.equal(merged.length, 1);
+  assert.equal(merged[0].content[0].text, '新文案');
+});
+
+test('mergeConversationSnapshot returns current when incoming is empty', () => {
+  const local = [msg('u1', 'user', 'hello')];
+  assert.deepEqual(mergeConversationSnapshot(local, []), local);
+});
+
+test('mergeSessionMessagesAfterFinish matches Finish sync merge semantics', () => {
+  const local = [
+    msg('u1', 'user', '根据图片做主题页'),
+    msg('a1', 'assistant', '已完成'),
+  ];
+  const server = [msg('u1', 'user', '根据图片做主题页')];
+  assert.deepEqual(
+    mergeSessionMessagesAfterFinish(local, server).map((message) => message.id),
+    ['u1', 'a1'],
+  );
+});