chore(tests): prune obsolete probes and define truthful offline test gates

scripts/rea/probe-library-open-local-20261017.json

@@ -1,25 +0,0 @@
-{
-  "include_fonts": false,
-  "track_selectors": [
-    ".conversation-list-tab-button",
-    ".library-page",
-    ".library-nav-item",
-    ".my-files-flat-row--file",
-    ".my-files-flat-col-actions"
-  ],
-  "actions": [
-    {
-      "kind": "click",
-      "step_id": "open-library",
-      "selector": ".conversation-list-tab-button",
-      "index": 4,
-      "frames": 1
-    },
-    {
-      "kind": "wait",
-      "step_id": "library-ready",
-      "duration_ms": 450,
-      "frames": 1
-    }
-  ]
-}