feat(events): application enrollment with form builder

[danielhe4rt]

Parent

#237

What to build

Implement the Application enrollment method: participant fills a dynamic form, enrollment goes to pending, organizer approves or rejects in Admin panel.

Dynamic form schema:

• events_enrollment_policies.application_form_schema stores a JSONB array defining form fields
• Schema structure: [{type: "text|textarea|select|checkbox", label: "...", required: bool, options?: [...]}]
• Filament form builder in Admin for organizer to define questions when creating/editing the policy
• App panel renders the form dynamically from the schema using Filament form components

Modify EnrollUserAction (application path):

• When enrollment_method = 'application':
  • Validates submitted data against the form schema
  • Creates enrollment with status pending, stores answers in application_data (JSONB)
  • Records transition (from=null, to=pending, triggered_by=user)
  • Does NOT check capacity yet (only checked on approval)

Action: ApproveApplicationAction

• Validates: enrollment status must be pending
• Checks capacity (with lockForUpdate) — if full + has_waitlist → waitlisted, if full + no waitlist → reject approval
• Transitions to confirmed (or waitlisted), sets confirmed_at
• Records transition (triggered_by=admin, actor_user_id=organizer)
• Dispatches EnrollmentConfirmed domain event

Action: RejectApplicationAction

• Validates: enrollment status must be pending
• Transitions to rejected, stores rejection_reason
• Records transition (triggered_by=admin, actor_user_id=organizer, reason=rejection_reason)

Admin panel:

• "Pending Applications" view/filter on enrollments — shows application_data in a readable format
• "Approve" and "Reject" actions (reject requires reason text field)
• Application data displayed in enrollment detail view

App panel:

• Dynamic form rendered from policy schema when user clicks "Apply"
• Shows "Application pending" status with submitted data (read-only)
• Shows "Rejected" status with rejection reason when applicable

Acceptance criteria

• Organizer can define a dynamic form schema via Filament form builder in Admin
• Participant sees and fills the dynamic form in App panel
• Submission creates enrollment with status pending and application_data populated
• Organizer can approve → enrollment transitions to confirmed (or waitlisted if full)
• Organizer can reject with reason → enrollment transitions to rejected with reason stored
• Capacity is checked on approval, not on submission
• Application data is displayed in Admin enrollment detail
• Transition audit trail records approver/rejector identity
• Feature tests: submit application, approve, reject, approve when full (waitlist), approve when full (no waitlist)
• Pint passes

Blocked by

• feat(events): RSVP enrollment end-to-end #240 (RSVP Enrollment — shares EnrollUserAction base)