fix(acceptance): 首轮 Windows 验收 7 项缺陷回修（docs/14）

P0 快捷键让行判定补 recoveryDismissed，点过「稍后再说」不再全失效；
P1 冲突重载加 force 绕过防竞态守卫；路径分隔符 joinPath 原生化 +
samePath 归一化比较；.source-cm 补文档字色；
P2 turndown 启用 GFM 插件（HTML 导入不再丢表格）；任务复选框去掉
click preventDefault（浏览器激活撤销覆盖视觉同步）；
P3 新增 syncEditorContent：干净标签的挂载/卸载序列化回写同步基线，
切标签不再误标未保存。vitest 74 通过 + 2 跳过。

package-lock.json

@@ -29,6 +29,7 @@
         "remark-rehype": "11.1.2",
         "shiki": "4.6.0",
         "turndown": "7.2.2",
+        "turndown-plugin-gfm": "^1.0.2",
         "unified": "11.0.5",
         "unist-util-visit": "5.1.0"
       },
@@ -7239,6 +7240,12 @@
         "@mixmark-io/domino": "^2.2.0"
       }
     },
+    "node_modules/turndown-plugin-gfm": {
+      "version": "1.0.2",
+      "resolved": "https://registry.npmjs.org/turndown-plugin-gfm/-/turndown-plugin-gfm-1.0.2.tgz",
+      "integrity": "sha512-vwz9tfvF7XN/jE0dGoBei3FXWuvll78ohzCZQuOb+ZjWrs3a0XhQVomJEb2Qh4VHTPNRO4GPZh0V7VRbiWwkRg==",
+      "license": "MIT"
+    },
     "node_modules/typescript": {
       "version": "5.6.3",
       "resolved": "https://registry.npmjs.org/typescript/-/typescript-5.6.3.tgz",