feat: comprehensive audio system and MCP server implementation

Audio System Enhancements:
- Complete PipeWire configuration with WirePlumber session management
- AI-powered noise suppression using RNNoise plugin
- GUI applications: EasyEffects, pavucontrol, Helvum, qpwgraph, pwvucontrol
- Pre-configured audio presets for microphone noise suppression
- Desktop integration with auto-start and helper scripts
- Validation tools and interactive audio management utilities
- Real-time audio processing with RTKit optimization
- Cross-application compatibility (Discord, Zoom, OBS, etc.)

MCP (Model Context Protocol) Implementation in Guile Scheme:
- Modular MCP server architecture with clean separation of concerns
- JSON-RPC transport layer with WebSocket and stdio support
- Protocol compliance with MCP specification
- Comprehensive error handling and validation
- Router system for tool and resource management
- Integration layer for NixOS Home Lab management
- Full test suite with unit and integration tests
- Documentation and usage examples

Technical Details:
- Removed conflicting ALSA udev rules while maintaining compatibility
- Fixed package dependencies and service configurations
- Successfully deployed and tested on congenital-optimist machine
- Functional programming approach using Guile Scheme modules
- Type-safe protocol implementation with validation
- Async/await pattern support for concurrent operations

This represents a significant enhancement to the Home Lab infrastructure,
providing both professional-grade audio capabilities and a robust MCP
server implementation for AI assistant integration.

packages/mcp-server/howto.md

@@ -0,0 +1,16 @@
+# Run all tests
+make test
+
+# Run specific test types
+make test-unit
+make test-integration
+make test-compliance
+
+# Check syntax
+make check-syntax
+
+# Continuous testing
+make test-watch
+
+# Generate reports
+make test-report