Conductor workspaces symlink `.agents` from KTX_AGENT_OVERLAYS_ROOT, which
Codex CLI reads directly. Claude Code only scans `.claude/skills/`, so the
shared skills were invisible to it. Add `link_agent_skills_for_claude` to
mirror each `.agents/skills/*` entry as a symlink under `.claude/skills/*`.
Idempotent and refuses to clobber existing non-matching entries.