feat: comprehensive test infrastructure improvements

- Fix unit test imports: add env setup in conftest.py before module imports
- Add 24 new auth router tests (RBAC, preferences, password validation)
- Add 16 new tests for litellm and chat_summary routers
- Apply black formatting and ruff linting across codebase
- Add pre-commit hooks configuration (black, ruff, file checks)
- Increase CI coverage threshold from 40% to 50%

Test Results:
- 206 tests passing (91 unit + 115 integration)
- Coverage: 58.79% on core modules
- auth.py: 57% → 85%, litellm.py: 23% → 87%, chat_summary.py: 41% → 100%
- auth_service: 96.51%, config: 100%, rbac: 93.48%

dashboard/backend/tests/integration/test_system.py

@@ -1,9 +1,11 @@
 """
 Integration tests for system operations.
 """
-import pytest
+
 import os
-from unittest.mock import patch, Mock
+from unittest.mock import Mock, patch
+
+import pytest
 
 
 class TestSystemStats:
@@ -17,7 +19,7 @@ class TestSystemStats:
         mock_disk.used = 500000000000
         mock_disk.free = 500000000000
 
-        with patch('shutil.disk_usage', return_value=mock_disk):
+        with patch("shutil.disk_usage", return_value=mock_disk):
             response = test_app.get("/api/system/stats", headers=admin_headers)
 
         assert response.status_code == 200
@@ -81,11 +83,7 @@ class TestAuditLog:
 
     def test_get_audit_log_with_limit(self, test_app, admin_headers, temp_volume_root):
         """Test getting audit log with line limit."""
-        response = test_app.get(
-            "/api/system/audit-log",
-            headers=admin_headers,
-            params={"lines": 50}
-        )
+        response = test_app.get("/api/system/audit-log", headers=admin_headers, params={"lines": 50})
 
         assert response.status_code == 200
         data = response.json()
@@ -104,22 +102,14 @@ class TestNotification:
     @pytest.mark.skip(reason="Requires Telegram bot token and makes external API call")
     def test_send_notification_success(self, test_app, admin_headers):
         """Test sending a notification."""
-        response = test_app.post(
-            "/api/system/notify",
-            headers=admin_headers,
-            json={"message": "Test notification"}
-        )
+        response = test_app.post("/api/system/notify", headers=admin_headers, json={"message": "Test notification"})
 
         # This will fail without proper Telegram config
         assert response.status_code in [200, 400]
 
     def test_send_notification_without_message(self, test_app, admin_headers):
         """Test sending notification without message."""
-        response = test_app.post(
-            "/api/system/notify",
-            headers=admin_headers,
-            json={}
-        )
+        response = test_app.post("/api/system/notify", headers=admin_headers, json={})
 
         assert response.status_code == 200
         data = response.json()
@@ -127,10 +117,7 @@ class TestNotification:
 
     def test_send_notification_without_auth(self, test_app):
         """Test sending notification without authentication."""
-        response = test_app.post(
-            "/api/system/notify",
-            json={"message": "Test"}
-        )
+        response = test_app.post("/api/system/notify", json={"message": "Test"})
 
         assert response.status_code == 401
 
@@ -140,6 +127,7 @@ class TestOpenClawToken:
 
     def test_get_openclaw_token_as_admin(self, test_app, admin_headers, mock_config, monkeypatch):
         """Test getting OpenClaw token as admin from LAN."""
+
         # Mock the IP check to return a LAN IP
         def mock_get_client_ip(request):
             return "192.168.1.100"
@@ -148,6 +136,7 @@ class TestOpenClawToken:
             return True
 
         import config
+
         monkeypatch.setattr(config, "get_client_ip", mock_get_client_ip)
         monkeypatch.setattr(config, "is_lan_ip", mock_is_lan_ip)
 
@@ -159,6 +148,7 @@ class TestOpenClawToken:
 
     def test_get_openclaw_token_non_lan(self, test_app, admin_headers, monkeypatch):
         """Test getting OpenClaw token from non-LAN IP."""
+
         # Mock the IP check to return a non-LAN IP
         def mock_get_client_ip(request):
             return "1.2.3.4"
@@ -167,6 +157,7 @@ class TestOpenClawToken:
             return False
 
         import config
+
         monkeypatch.setattr(config, "get_client_ip", mock_get_client_ip)
         monkeypatch.setattr(config, "is_lan_ip", mock_is_lan_ip)
 
@@ -176,12 +167,12 @@ class TestOpenClawToken:
 
     def test_get_openclaw_token_as_member(self, test_app, mock_config, temp_auth_file, temp_rbac_file):
         """Test that non-admin cannot get OpenClaw token."""
-        from auth_service import create_access_token
         from datetime import timedelta
 
+        from auth_service import create_access_token
+
         member_token = create_access_token(
-            data={"sub": "memberuser", "role": "member"},
-            expires_delta=timedelta(minutes=30)
+            data={"sub": "memberuser", "role": "member"}, expires_delta=timedelta(minutes=30)
         )
         headers = {"Authorization": f"Bearer {member_token}"}