Shared Files sort can retain stale rows after backing data changes

Summary¶

The Shared Files list could sort while its row payloads still referenced files that had already left the live shared-file list.

Landed on main in commit 8a2588a (BUG-038 prune stale shared-files rows before sort).

The fix prunes stale Shared Files rows before sorting, reducing stale pointer exposure during shared-list churn.