feat: add kiosk settings UI and co-managed client filtering

- Created kiosk_settings table for configuration storage
- Added API endpoints for kiosk settings (GET/POST)
- Filter out co-managed clients (configurable company exclusions)
- Built comprehensive settings UI at /kiosk/settings
- Allow excluding specific companies from kiosk display
- Configurable cycle interval, refresh interval, and RMM alert toggle
- Updated dashboard link to point to settings page
- Applied company exclusion filter to all ticket queries and activity feed
- Default excludes Thrasher Group (ID: 29861361)

app/dashboard/page.tsx

@@ -103,11 +103,11 @@ export default function DashboardPage() {
     },
     {
       title: 'Kiosk Display',
-      description: 'Full-screen executive dashboard for TV display',
-      href: '/kiosk',
+      description: 'Configure and view executive dashboard for TV',
+      href: '/kiosk/settings',
       icon: Activity,
       color: 'blue',
-      stats: 'Live metrics display'
+      stats: 'Settings & display'
     },
     {
       title: 'Sync Management',