feat: add Cloudron packaging templates

- Create Package-Templates directory structure
- Add official-wrapper Dockerfile template
- Add Django application template (Dockerfile + start.sh)
- Add README template with comprehensive documentation
- Create template usage documentation

Templates include:
- Official Image Wrapper pattern (simple wrapper for existing images)
- Django Application pattern (with PostgreSQL integration)
- Standardized README template with all sections
- Django start.sh with database wait, migrations, admin creation
- Template documentation and usage instructions

Benefits:
- Accelerates packaging for similar applications
- Ensures consistency across packages
- Reduces repetitive work
- Documents Cloudron best practices
- Reference for future packaging

Template patterns covered:
- Official image wrapper
- Django application with PostgreSQL
- Database wait logic
- Migration execution
- Admin user creation
- Health check implementation
- Environment variable configuration

💘 Generated with Crush

Assisted-by: GLM-4.7 via Crush <crush@charm.land>

Package-Templates/README.template.md

@@ -0,0 +1,142 @@
+# <APP_NAME> Cloudron Package
+
+## Description
+
+<Brief description of application and its purpose>
+
+## Features
+
+### Core Capabilities
+- **Feature 1**: Description
+- **Feature 2**: Description
+- **Feature 3**: Description
+
+### Application Features
+- **Feature A**: Description with details
+- **Feature B**: Description with details
+- **Feature C**: Description with details
+
+## Configuration
+
+### Environment Variables
+
+#### Application Configuration
+- `CONFIG_VAR_1`: Description (default: value1)
+- `CONFIG_VAR_2`: Description (default: value2)
+
+### Ports
+- **8080**: Main HTTP port (description)
+
+### Addons
+- **PostgreSQL**: Required for database storage
+- **Localstorage**: Used for file storage
+- **Redis**: Optional caching
+
+## Usage
+
+### 1. Initial Setup
+
+1. Open <APP_NAME>
+2. Create admin account (if applicable)
+3. Configure system settings
+4. Verify application is running
+
+### 2. Basic Usage
+
+**Step 1**: Do something
+1. Navigate to section
+2. Click button
+3. Configure settings
+4. Save
+
+**Step 2**: Do something else
+1. Use feature
+2. Configure options
+3. Test functionality
+
+### 3. Configuration
+
+```bash
+# Example configuration
+CONFIG_VAR_1=value1
+CONFIG_VAR_2=value2
+```
+
+### 4. API Usage (if applicable)
+
+```bash
+# Example API call
+curl -X POST http://localhost:8080/api/endpoint \
+  -H "Content-Type: application/json" \
+  -d '{"key": "value"}'
+```
+
+## Architecture
+
+```
+                    ┌─────────────┐
+                    │   Client    │
+                    │  (Browser)   │
+                    └──────┬──────┘
+                           │
+                    HTTP Request
+                           ▼
+                   ┌──────────────┐
+                   │ <APP_NAME>   │
+                   │  (<TYPE>)     │
+                   │  Application   │
+                   └──────┬──────┘
+                           │
+              ┌────────────┼────────────┐
+              │            │            │
+              ▼            ▼            ▼
+       ┌──────────┐  ┌──────────┐  ┌──────────┐
+       │ Database  │  │ Storage   │  │  Cache    │
+       │ (PostgreSQL│  │  (Local   │  │  (Redis)  │
+       │            │  │  storage)  │  │            │
+       └──────────┘  └──────────┘  └──────────┘
+```
+
+## Security
+
+### Authentication
+- User management
+- Role-based access control (if applicable)
+- Session management
+- API token authentication (if applicable)
+
+### Data Protection
+- <Security feature 1>
+- <Security feature 2>
+- <Security feature 3>
+
+## Troubleshooting
+
+### Issue 1
+**Problem**: Description
+**Solution**: Steps to resolve
+**Check**: Verify by doing X
+
+### Issue 2
+**Problem**: Description
+**Solution**: Steps to resolve
+**Check**: Verify by doing Y
+
+## Documentation
+
+For more information:
+- [Official Website](https://example.com)
+- [GitHub Repository](https://github.com/example/app)
+- [Documentation](https://docs.example.com)
+
+## Support
+
+For issues and questions:
+- [GitHub Issues](https://github.com/example/app/issues)
+- [Discord Server](https://discord.gg/example)
+- [Forum](https://forum.example.com)
+
+## Upstream
+
+[GitHub Repository](https://github.com/example/app)
+[Official Website](https://example.com)