Context
runInstaller() in skill.ts spawns npx skills add; on a Bun-only machine without Node, the spawn error is swallowed into a bare non-ok result.
Task
Surface the spawn error with a hint ('npx not found: install Node or run bunx skills add ... manually').
Acceptance criteria
Forced spawn failure shows the actionable message.
Context
runInstaller()inskill.tsspawnsnpx skills add; on a Bun-only machine without Node, the spawn error is swallowed into a bare non-ok result.Task
Surface the spawn error with a hint ('npx not found: install Node or run bunx skills add ... manually').
Acceptance criteria
Forced spawn failure shows the actionable message.