Final-review-driven changes (Tasks 6/M1, I1 from the ledger):
- Drop the redundant abilities-list check in CombatEngine::useAbility.
By construction (Scenario::__construct enforces the allowlist), any
ability the unit 'knows' is also archetype-allowed; the second check
alone is sufficient and removes a dead code path.
- Update testUseAbilityRejectsAnAbilityTheArchetypeForbids to assert the
'Unit archetype forbids that ability.' message it actually exercises.
- Compute $template once in Scenario::__construct's per-unit loop and
drop the redundant catalog lookup on the next line.
Keith Solomon