Registers HuntingModule (POST /api/hunts) into the DI graph alongside its
new entities, and adds possibleMonsters (enabled LocationMonster pool,
weight-descending, empty when hunting is disabled) to
WorldService.getCurrentLocation. Also updates the pre-existing
DB-less app.e2e-spec.ts to override HuntingModule the same way the other
feature modules already are, since it now needs a real DataSource.