Personal skill has no manageable/removable source and silently serves stale content

A own self-created skill is available via the Skill tool in my session, but:

1. No backing file exists anywhere on disk — checked exhaustively: project .claude/skills/, user-level ~/.claude/skills/ (all subfolders), Claude Desktop's AppData\Roaming\Claude (including local-agent-mode-sessions), and all plugin caches. Nothing.
2. It's not visible in the Skills settings UI either, under "Personal skills" for any project workspace checked (only learn, a first-party skill, shows there).
3. Content is frozen/stale ("Last updated: 2026-06-09") and doesn't reflect any edits made since.
4. No management path exists to view, edit, update, or delete it — not via the filesystem, not via Settings → Skills, not via the project workspace switcher.

Workaround used: created a new project-level skill under a different name to avoid the naming collision, since the original name still resolves to stale content and can't be fixed or removed.

Impact: a user could easily keep getting outdated skill output indefinitely with no error, warning, or visible way to notice or fix it — the skill works, it just silently serves wrong/old content.

Environment: Claude Desktop (Windows), project-based workspace, "Local Agent Mode."