Update Claude.md to reference skills with brief overviews

Replace detailed instructions with skill references and 2-3 sentence overviews for:
- Docker Environment → /docker-setup
- Testing → /run-tests
- Code Quality → /static-analysis
- Adding New Modules → /create-module
- Database Operations → /database-operations
- Debugging → /debug-setup
- Troubleshooting Docker → /troubleshoot-docker

This reduces duplication and keeps Claude.md concise while maintaining comprehensive guidance through skills.

Claude.md

@@ -155,55 +155,29 @@ Commands (write operations) and Queries (read operations) are separated:
 
 ### Docker Environment
 
-All development happens in Docker containers:
+See skill: `/docker-setup` for detailed instructions.
 
-```bash
-# Start environment
-make up
-
-# Install dependencies
-make install
-
-# Access container shell
-make shell
-```
-
-**Available Services:**
-- **App**: PHP 8.1 + Apache (http://localhost:8000)
-- **Database**: MySQL 8.0 (port 3306)
-- **phpMyAdmin**: Database management (http://localhost:8080)
+All development happens in Docker containers with PHP 8.1, MySQL 8.0, and phpMyAdmin. Use `make up` to start the environment and `make install` to install dependencies.
 
 ### Testing
 
-Comprehensive testing suite with PHPUnit:
+See skill: `/run-tests` for detailed instructions.
 
-```bash
-make test              # Run all tests
-make test-unit         # Unit tests only
-make test-integration  # Integration tests only
-make test-coverage     # Coverage report
-```
+Comprehensive testing suite with PHPUnit supporting unit tests, integration tests, and coverage reports. Use `make test` to run all tests.
 
 ### Code Quality
 
-Static analysis and code quality tools:
+See skill: `/static-analysis` for detailed instructions.
 
-```bash
-make phpstan           # PHPStan static analysis
-make deptrac           # Deptrac layer analysis
-make static-analysis   # Run both
-make rector            # Preview Rector changes
-make rector-fix        # Apply Rector changes
-```
+Static analysis with PHPStan and Deptrac to enforce type safety and architectural boundaries. Use `make static-analysis` to run both tools.
 
 ## Important Patterns
 
 ### Adding New Modules
 
-1. Create directory: `src/Modules/{ModuleName}/`
-2. Implement Domain, Application, and Infrastructure layers
-3. Create `{ModuleName}ServiceProvider.php` in module root
-4. ModuleLoader automatically discovers and registers it
+See skill: `/create-module` for detailed instructions.
+
+Create modules following DDD principles with Domain, Application, and Infrastructure layers. The ModuleLoader automatically discovers service providers in `src/Modules/*/`.
 
 ### Creating Service Provider
 
@@ -283,11 +257,9 @@ APP_SUPPORTED_LOCALES=en,de,fr
 
 ## Debugging
 
-Xdebug is configured for debugging:
+See skill: `/debug-setup` for detailed instructions.
 
-- Set breakpoints in IDE
-- Access application via http://localhost:8000
-- Debug sessions automatically connect on port 9003
+Xdebug is pre-configured in the Docker environment for PHPStorm and VS Code. Debug sessions connect on port 9003 with automatic path mapping to `/var/www/html`.
 
 ## Documentation
 
@@ -332,15 +304,12 @@ make rector          # Code quality preview
 ```
 
 **Database:**
+
+See skill: `/database-operations` for detailed instructions.
+
 ```bash
 # Import schema
 docker compose exec -T db mysql -u foundation_user -pfoundation_password foundation < database/schema.sql
-
-# Access MySQL CLI
-docker compose exec db mysql -u foundation_user -p foundation
-
-# Export database
-docker compose exec db mysqldump -u foundation_user -pfoundation_password foundation > backup.sql
 ```
 
 ## Best Practices
@@ -360,9 +329,9 @@ docker compose exec db mysqldump -u foundation_user -pfoundation_password founda
 
 ### Docker Issues
 
-- Ensure Docker and Docker Compose are installed
-- Check port conflicts (8000, 8080, 3306)
-- Verify user permissions: `export USER_ID=$(id -u) && export GROUP_ID=$(id -g)`
+See skill: `/troubleshoot-docker` for detailed diagnostic steps and solutions.
+
+Common issues include port conflicts (8000, 8080, 3306), permission errors, and container startup failures. Use `docker compose ps` and `docker compose logs` to diagnose problems.
 
 ### Database Connection Issues