908-line lib/actions/classes.ts → lib/actions/classes/{definitions,sessions,
signups,instructor}.ts ('use server') + _guard.ts (requirePermission/Gate) +
_forms.ts (findSpaceForm/hasFormSubmission) + a plain index.ts barrel. All 14
actions preserved verbatim; lib/actions/index.ts unchanged. Helpers stay
internal (not re-exported). tsc 0, tests green.
Co-Authored-By: Claude Opus 4.8 (1M context) <[email protected]>