Implements the offerings catalog (#1): private-lesson types and group
classes carrying pricing, billing mode (one_time/full_term), duration,
capacity, and term details. Adds the src/Offering/ domain (value object,
repository, REST endpoint, admin controller + template), the us_offerings
table, and an Offerings admin page.
Also lands the capability slice of #9: registers the us_studio_admin role
and the new capability strings (manage_instructors, manage_offerings,
manage_questions, manage_policies, manage_billing, view_all_payments,
view_own_payments, export_payments) so offering management gates correctly.
Tests: tests/Unit/Offering/ (value object + repository) and a studio-admin
case in RoleManagerTest. composer test, cs, and PHPStan level 6 all pass.
Refs #1#9
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
