fix(server): show new skills in the picker without restarting

[dakdevs]

Why

The $ picker keeps the first skill snapshot for a workspace until T3 restarts.

Evidence:

• refreshWorkspaceSnapshot returns the cached list once a cwd snapshot exists, so a later composer open does not scan again.
• Web and mobile only request that snapshot when the cwd is missing from workspaceSnapshots.
• The 5-minute health probe updates machine-level skills, but the composer reads workspaceSnapshots[cwd].skills first.

Fix: Watch the skill files and folders Claude, Cursor, and Antigravity already look at. If a root is missing, watch the nearest existing parent so creating that folder still fires. Refresh when a skill file there changes, or when a directory on the path to a missing root appears. Keep the last complete catalog until that refresh succeeds.

Summary

Skills show up in $ and / when the files we already look for change. How skills are found does not change.

What

• Claude, Cursor, and Antigravity expose the roots they already load via skillCatalogRoots.
• Existing roots are watched recursively. Missing roots retarget when they appear.
• A failed refresh leaves the previous complete catalog in place.

Who this helps

Anyone who adds or edits a skill while T3 is already open: installing a skill mid-session, an agent writing SKILL.md, or copying a folder into .claude/skills / .agents/skills.

Test plan

• Open a thread so a workspace snapshot exists, add a skill folder under a provider root, open $, and confirm the new skill appears without restarting.
• Edit that skill's SKILL.md and confirm the picker reflects the change without restarting.
• Same path with /.
• Repeat on mobile New task and an existing thread.

[github-actions]

Thread transfer impact

⚠️ The latest CI run did not produce a thread transfer result for d890c03.

This comment will update automatically after the next completed run.