refactor: restructure cursor rules with new meta-rule architecture

- Remove legacy rule files (documentation.mdc, general_development.mdc, etc.)
- Implement new meta-rule system with core, app, and feature categories
- Add meta-rule files for different workflows (bug diagnosis, feature planning, etc.)
- Create organized directory structure: core/, app/, features/, database/, etc.
- Add comprehensive README.md for rules documentation
- Establish new rule architecture with always-on and workflow-specific rules

This restructuring improves rule organization, enables better workflow management,
and provides clearer separation of concerns for different development tasks.

.cursor/rules/features/camera-implementation.mdc

@@ -0,0 +1,163 @@
+# Camera Implementation Documentation
+
+## Overview
+
+This document describes how camera functionality is implemented across the
+TimeSafari application. The application uses cameras for two main purposes:
+
+1. QR Code scanning
+
+2. Photo capture
+
+## Components
+
+### QRScannerDialog.vue
+
+Primary component for QR code scanning in web browsers.
+
+**Key Features:**
+
+- Uses `qrcode-stream` for web-based QR scanning
+
+- Supports both front and back cameras
+
+- Provides real-time camera status feedback
+
+- Implements error handling with user-friendly messages
+
+- Includes camera switching functionality
+
+**Camera Access Flow:**
+
+1. Checks for camera API availability
+
+2. Enumerates available video devices
+
+3. Requests camera permissions
+
+4. Initializes camera stream with preferred settings
+
+5. Handles various error conditions with specific messages
+
+### PhotoDialog.vue
+
+Component for photo capture and selection.
+
+**Key Features:**
+
+- Cross-platform photo capture interface
+
+- Image cropping capabilities
+
+- File selection fallback
+
+- Unified interface for different platforms
+
+## Services
+
+### QRScanner Services
+
+#### WebDialogQRScanner
+
+Web-based implementation of QR scanning.
+
+**Key Methods:**
+
+- `checkPermissions()`: Verifies camera permission status
+
+- `requestPermissions()`: Requests camera access
+
+- `isSupported()`: Checks for camera API support
+
+- Handles various error conditions with specific messages
+
+#### CapacitorQRScanner
+
+Native implementation using Capacitor's MLKit.
+
+**Key Features:**
+
+- Uses `@capacitor-mlkit/barcode-scanning`
+
+- Supports both front and back cameras
+
+- Implements permission management
+
+- Provides continuous scanning capability
+
+### Platform Services
+
+#### WebPlatformService
+
+Web-specific implementation of platform features.
+
+**Camera Capabilities:**
+
+- Uses HTML5 file input with capture attribute
+
+- Falls back to file selection if camera unavailable
+
+- Processes captured images for consistent format
+
+#### CapacitorPlatformService
+
+Native implementation using Capacitor.
+
+**Camera Features:**
+
+- Uses `Camera.getPhoto()` for native camera access
+
+- Supports image editing
+
+- Configures high-quality image capture
+
+- Handles base64 image processing
+
+#### ElectronPlatformService
+
+Desktop implementation (currently unimplemented).
+
+---
+
+**See also**:
+
+- `.cursor/rules/features/camera_technical.mdc` for
+
+  detailed technical implementation
+
+- `.cursor/rules/features/camera_platforms.mdc` for platform-specific details
+
+**Status**: Active camera implementation overview
+**Priority**: Medium
+**Estimated Effort**: Ongoing reference
+**Dependencies**: None
+**Stakeholders**: Development team, Camera feature team
+
+- iOS and Android devices
+
+- Desktop platforms
+
+- Various network conditions
+
+## Model Implementation Checklist
+
+### Before Camera Implementation
+
+- [ ] **Platform Analysis**: Understand camera requirements across all platforms
+- [ ] **Feature Planning**: Plan QR scanning and photo capture features
+- [ ] **Service Planning**: Plan camera service architecture
+- [ ] **Testing Strategy**: Plan testing across web, mobile, and desktop
+
+### During Camera Implementation
+
+- [ ] **Component Development**: Implement QRScannerDialog and PhotoDialog
+- [ ] **Service Implementation**: Implement platform-specific camera services
+- [ ] **Permission Handling**: Implement proper camera permission management
+- [ ] **Error Handling**: Implement graceful error handling for camera failures
+
+### After Camera Implementation
+
+- [ ] **Cross-Platform Testing**: Test camera functionality across all platforms
+- [ ] **Feature Validation**: Verify QR scanning and photo capture work correctly
+- [ ] **Performance Testing**: Ensure camera performance meets requirements
+- [ ] **Documentation Update**: Update camera implementation documentation