Fix Work Hub session inventory (#2268)

Port the app workspace and runtime session inventory fixes from the personal James Hub canvas into the generic Work Hub extension. This lets the cleanup and recent-session surfaces read current app workspaces before falling back to the legacy session store.

Co-authored-by: Copilot App <223556219+Copilot@users.noreply.github.com>

extensions/work-hub/extension.mjs

@@ -14,6 +14,7 @@ import {
     readConfig,
     getItemDetail,
     runItemAction,
+    setCopilotSession,
 } from "./data.mjs";
 import { renderHtml } from "./renderer.mjs";
 
@@ -374,3 +375,4 @@ sessionRef = await joinSession({
         }),
     ],
 });
+setCopilotSession(sessionRef);