feat: Add time block approval workflow and staff permission system

- Add TimeBlock approval status with manager approval workflow
- Create core mixins for staff permission restrictions (DenyStaffWritePermission, etc.)
- Add StaffDashboard page for staff-specific views
- Refactor MyAvailability page for time block management
- Update field mobile status machine and views
- Add per-user permission overrides via JSONField
- Document core mixins and permission system in CLAUDE.md

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

frontend/src/api/auth.ts

@@ -72,6 +72,8 @@ export interface User {
   permissions?: Record<string, boolean>;
   can_invite_staff?: boolean;
   can_access_tickets?: boolean;
+  can_edit_schedule?: boolean;
+  linked_resource_id?: number;
   quota_overages?: QuotaOverage[];
 }