Add Home Assistant development environment to flake

- Add home-assistant and mosquitto to dev shell
- Create minimal dev-config/ for HA development instance
- Symlink custom integration for easy testing
- Add HA dev files to .gitignore
- No HA codebase committed, just references via Nix

Usage:
  nix develop
  hass --config ./dev-config

Features:
- Isolated from production HA instance
- MQTT broker for testing
- Debug logging enabled
- In-memory database for fast iteration

.gitignore

@@ -28,3 +28,9 @@ system_stats_daemon-*.tar
 # Nix result symlinks
 result
 result-*
+
+# Home Assistant development files
+dev-config/.storage/
+dev-config/home-assistant.log*
+dev-config/deps/
+dev-config/.cloud/

dev-config/automations.yaml

@@ -0,0 +1,2 @@
+# Development automations for testing Systant integration
+[]

dev-config/configuration.yaml

@@ -0,0 +1,47 @@
+# Home Assistant Development Configuration for Systant Integration
+
+homeassistant:
+  name: Systant Development
+  latitude: 0
+  longitude: 0
+  elevation: 0
+  unit_system: metric
+  time_zone: UTC
+  
+# Enable configuration UI
+config:
+
+# Enable frontend
+frontend:
+  themes: !include_dir_merge_named themes
+
+# Enable API
+api:
+
+# Enable system health
+system_health:
+
+# Enable mobile app support
+mobile_app:
+
+# MQTT Configuration (connect to local broker)
+mqtt:
+  broker: localhost
+  port: 1883
+  discovery: true
+  discovery_prefix: homeassistant
+
+# Enable logging
+logger:
+  default: info
+  logs:
+    custom_components.systant: debug
+    homeassistant.components.mqtt: debug
+
+# Enable recorder with in-memory database for development
+recorder:
+  db_url: "sqlite:///:memory:"
+  purge_keep_days: 1
+
+# Enable default integrations
+default_config:

dev-config/scenes.yaml

@@ -0,0 +1,2 @@
+# Development scenes for testing Systant integration
+[]

dev-config/scripts.yaml

@@ -0,0 +1,2 @@
+# Development scripts for testing Systant integration
+{}

flake.nix

@@ -41,23 +41,33 @@
             python311Packages.pip
             python311Packages.ipython
             python311Packages.pytest
-            python311Packages.homeassistant
             python311Packages.pytest-homeassistant-custom-component
             python311Packages.black
             python311Packages.isort
             python311Packages.flake8
             python311Packages.mypy
+            
+            # Home Assistant for development
+            home-assistant
+            mosquitto
           ];
 
           shellHook = ''
             echo "Systant development environment loaded"
             echo "Elixir: $(elixir --version | head -1)"
             echo "Python: $(python --version)"
-            echo "Available tools: pytest, black, isort, flake8, mypy"
+            echo "Home Assistant: $(hass --version)"
+            echo ""
+            echo "Available tools: pytest, black, isort, flake8, mypy, mosquitto"
             echo ""
             echo "Directories:"
             echo "  server/ - Elixir systant daemon"
             echo "  home-assistant-integration/ - Home Assistant custom integration"
+            echo "  dev-config/ - Home Assistant development configuration"
+            echo ""
+            echo "Commands:"
+            echo "  hass --config ./dev-config - Start HA dev instance"
+            echo "  mosquitto - Start MQTT broker for testing"
           '';
         };
         packages = {

server/dev-config/custom_components/systant

@@ -0,0 +1 @@
+../../home-assistant-integration/custom_components/systant