feat: Home Assistant integration — WebSocket connection, automation conditions, UI

Add full Home Assistant integration via WebSocket API:
- HARuntime: persistent WebSocket client with auth, auto-reconnect, entity state cache
- HAManager: ref-counted runtime pool (like WeatherManager)
- HomeAssistantCondition: new automation trigger type matching entity states
- REST API: CRUD for HA sources + /test, /entities, /status endpoints
- /api/v1/system/integrations-status: combined MQTT + HA dashboard indicators
- Frontend: HA Sources tab in Streams, condition type in automation editor
- Modal editor with host, token, SSL, entity filters
- websockets>=13.0 dependency added

server/src/wled_controller/api/schemas/home_assistant.py

@@ -0,0 +1,97 @@
+"""Home Assistant source schemas (CRUD + test + entities)."""
+
+from datetime import datetime
+from typing import List, Optional
+
+from pydantic import BaseModel, Field
+
+
+class HomeAssistantSourceCreate(BaseModel):
+    """Request to create a Home Assistant source."""
+
+    name: str = Field(description="Source name", min_length=1, max_length=100)
+    host: str = Field(description="HA host:port (e.g. '192.168.1.100:8123')", min_length=1)
+    token: str = Field(description="Long-Lived Access Token", min_length=1)
+    use_ssl: bool = Field(default=False, description="Use wss:// instead of ws://")
+    entity_filters: List[str] = Field(
+        default_factory=list, description="Entity ID filter patterns (e.g. ['sensor.*'])"
+    )
+    description: Optional[str] = Field(None, description="Optional description", max_length=500)
+    tags: List[str] = Field(default_factory=list, description="User-defined tags")
+
+
+class HomeAssistantSourceUpdate(BaseModel):
+    """Request to update a Home Assistant source."""
+
+    name: Optional[str] = Field(None, description="Source name", min_length=1, max_length=100)
+    host: Optional[str] = Field(None, description="HA host:port", min_length=1)
+    token: Optional[str] = Field(None, description="Long-Lived Access Token", min_length=1)
+    use_ssl: Optional[bool] = Field(None, description="Use wss://")
+    entity_filters: Optional[List[str]] = Field(None, description="Entity ID filter patterns")
+    description: Optional[str] = Field(None, description="Optional description", max_length=500)
+    tags: Optional[List[str]] = None
+
+
+class HomeAssistantSourceResponse(BaseModel):
+    """Home Assistant source response."""
+
+    id: str = Field(description="Source ID")
+    name: str = Field(description="Source name")
+    host: str = Field(description="HA host:port")
+    use_ssl: bool = Field(description="Whether SSL is enabled")
+    entity_filters: List[str] = Field(default_factory=list, description="Entity filter patterns")
+    connected: bool = Field(default=False, description="Whether the WebSocket connection is active")
+    entity_count: int = Field(default=0, description="Number of cached entities")
+    description: Optional[str] = Field(None, description="Description")
+    tags: List[str] = Field(default_factory=list, description="User-defined tags")
+    created_at: datetime = Field(description="Creation timestamp")
+    updated_at: datetime = Field(description="Last update timestamp")
+
+
+class HomeAssistantSourceListResponse(BaseModel):
+    """List of Home Assistant sources."""
+
+    sources: List[HomeAssistantSourceResponse] = Field(description="List of HA sources")
+    count: int = Field(description="Number of sources")
+
+
+class HomeAssistantEntityResponse(BaseModel):
+    """A single HA entity."""
+
+    entity_id: str = Field(description="Entity ID (e.g. 'sensor.temperature')")
+    state: str = Field(description="Current state value")
+    friendly_name: str = Field(description="Human-readable name")
+    domain: str = Field(description="Entity domain (e.g. 'sensor', 'binary_sensor')")
+
+
+class HomeAssistantEntityListResponse(BaseModel):
+    """List of entities from a HA instance."""
+
+    entities: List[HomeAssistantEntityResponse] = Field(description="List of entities")
+    count: int = Field(description="Number of entities")
+
+
+class HomeAssistantTestResponse(BaseModel):
+    """Connection test result."""
+
+    success: bool = Field(description="Whether connection and auth succeeded")
+    ha_version: Optional[str] = Field(None, description="Home Assistant version")
+    entity_count: int = Field(default=0, description="Number of entities found")
+    error: Optional[str] = Field(None, description="Error message if connection failed")
+
+
+class HomeAssistantConnectionStatus(BaseModel):
+    """Connection status for dashboard indicators."""
+
+    source_id: str
+    name: str
+    connected: bool
+    entity_count: int
+
+
+class HomeAssistantStatusResponse(BaseModel):
+    """Overall HA integration status for dashboard."""
+
+    connections: List[HomeAssistantConnectionStatus]
+    total_sources: int
+    connected_count: int