feat: implement member visibility dialog with checkbox selection and refresh

- Add "Set Visibility" dialog for meeting members who need visibility settings
- Filter members to show only those not in contacts or without seesMe set
- Implement checkbox selection with "Select All" functionality
- Add reactive checkbox behavior with proper state management
- Default all checkboxes to checked when dialog opens
- Implement "Set Visibility" action to add contacts and set seesMe property
- Add success notifications with count of affected members
- Disable "Set Visibility" button when no members are selected
- Use notification callbacks for data refresh
- Hide "Set Visibility" buttons when no members need visibility settings
- Add proper dialog state management and cleanup
- Ensure dialog closes before triggering data refresh to prevent stale states

The implementation provides a smooth user experience for managing member visibility settings with proper state synchronization between components.

src/views/NotFoundView.vue

@@ -60,7 +60,9 @@
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+                d="M3 12l2-2m0 0l7-7 7 7M5 10v10a1 1 0 001 1h3m10-11l2
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+                1 0 011 1v4a1 1 0 001 1m-6 0h6"
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