Milestone: open/freeze/undergoing/completed/closed (was open/pending/deferred/progressing/closed)
Task: open/pending/undergoing/completed/closed (was open/pending/progressing/closed)
- Add MilestoneStatusEnum to schemas with typed validation
- Add started_at field to Milestone model
- Update all router/CLI references from progressing->undergoing
- Add completed status handling in task transition logic
- Add Role model with 17 default permissions
- Add init_wizard to create admin/guest roles on first startup
- Protect admin role from modification/deletion via API
- Fix MilestoneCreate schema (project_id optional)
- Fix delete role to clean up role_permissions first
- Add check_project_role RBAC function
