feat: improve goal mode and Codex App resilience

.trellis/tasks/08-18-goal-mode-title/task.json

@@ -0,0 +1,32 @@
+{
+  "id": "goal-mode-title",
+  "name": "goal-mode-title",
+  "title": "修复 Goal 模式标记与自动标题",
+  "description": "",
+  "status": "in_progress",
+  "dev_type": null,
+  "scope": null,
+  "package": null,
+  "priority": "P2",
+  "creator": "shiyue",
+  "assignee": "shiyue",
+  "createdAt": "2026-08-18",
+  "completedAt": null,
+  "branch": null,
+  "base_branch": "main",
+  "worktree_path": null,
+  "commit": null,
+  "pr_url": null,
+  "subtasks": [],
+  "children": [],
+  "parent": null,
+  "relatedFiles": [
+    "public/app.js",
+    "public/style.css",
+    "public/index.html",
+    "server.js",
+    "scripts/regression.js"
+  ],
+  "notes": "Goal 用户气泡增加模式标记；默认标题由服务端旁路派生，手动标题受保护。",
+  "meta": {}
+}