feat: add dashboard API with quick links and widgets

- Dashboard domain with Quick Links CRUD + reorder endpoints
- Dashboard widgets management endpoints
- Database migrations for quick_links and dashboard_widgets tables
- Static file controller for Organizr widgets
- Default local user when OIDC is disabled
- Domain-based architecture refactor (src/domains/, src/shared/)
- Test suite updated for new structure (285 tests passing)

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

tests/test_homeassistant_client.py

@@ -3,13 +3,13 @@ import pytest
 from unittest.mock import patch, AsyncMock, MagicMock
 import httpx
 
-from src.clients.homeassistant_client import HomeAssistantClient, get_homeassistant_client
+from src.shared.clients.homeassistant_client import HomeAssistantClient, get_homeassistant_client
 
 
 class TestHomeAssistantClientInit:
     """Test HomeAssistantClient initialization."""
 
-    @patch("src.clients.homeassistant_client.settings")
+    @patch("src.shared.clients.homeassistant_client.settings")
     def test_uses_settings_defaults(self, mock_settings):
         """Client should use settings for defaults."""
         mock_settings.homeassistant_url = "http://ha.local:8123"
@@ -39,8 +39,8 @@ class TestHomeAssistantClientInit:
 
         assert client.base_url == "http://custom:8123"
 
-    @patch("src.clients.homeassistant_client.logger")
-    @patch("src.clients.homeassistant_client.settings")
+    @patch("src.shared.clients.homeassistant_client.logger")
+    @patch("src.shared.clients.homeassistant_client.settings")
     def test_warns_when_token_missing(self, mock_settings, mock_logger):
         """Client should warn when token is not configured."""
         mock_settings.homeassistant_url = "http://ha.local:8123"
@@ -462,7 +462,7 @@ class TestGetHomeAssistantClientSingleton:
     def test_returns_same_instance(self):
         """get_homeassistant_client should return singleton."""
         # Reset singleton
-        import src.clients.homeassistant_client as module
+        import src.shared.clients.homeassistant_client as module
         module._homeassistant_client = None
 
         client1 = get_homeassistant_client()