build: untrack generated skill symlinks + add skills dep to install-service
The two skill symlinks under journal/.agents/skills/ and
journal/.claude/skills/ are generated by `make skills` and wiped by
`make clean` — yet they were tracked in git. Any concurrent `make clean`
during an in-flight hopper lode produced a "dirty primary repo" state
that blocked the ship stage (hit today during lode eyceddz6).
Untrack them (gitignore /journal/* already covers new adds) and add
`skills` as a direct prerequisite on install-service to close the narrow
corner where symlinks get removed without .installed being invalidated.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>