fix(FN-3829): recover stale merging status and align chat sidebar search styling

- Add self-healing recovery for stale in-review merging statuses when no active merger owns the task
- Skip merge re-enqueue for tasks already marked with transient merging statuses and add regression coverage
- Wire active merge task ID provider through project runtime for safer stale-status detection
- Use chat-sidebar-search-container in ChatView with matching CSS padding
- Normalize fusion-plugin-reports test script to use local vitest and add changeset for @runfusion/fusion patch

Fusion-Task-Id: FN-3829

plugins/fusion-plugin-reports/package.json

@@ -12,7 +12,7 @@
   },
   "scripts": {
     "build": "tsc",
-    "test": "pnpm dlx vitest run --silent=passed-only --reporter=dot"
+    "test": "vitest run --silent=passed-only --reporter=dot"
   },
   "dependencies": {
     "@fusion/core": "workspace:*",