style: apply black and isort formatting across entire codebase

- Standardize quote style (single to double quotes)
- Reorder and group imports alphabetically
- Fix line breaks and indentation for consistency
- Apply PEP 8 formatting standards

Also updated Makefile to exclude both venv and .venv from code quality checks.

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

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

tests/integration/api/v1/test_auth_endpoints.py

@@ -1,7 +1,8 @@
 # tests/integration/api/v1/test_auth_endpoints.py
+from datetime import datetime, timedelta, timezone
+
 import pytest
 from jose import jwt
-from datetime import datetime, timedelta, timezone
 
 
 @pytest.mark.integration
@@ -178,8 +179,7 @@ class TestAuthenticationAPI:
     def test_get_current_user_invalid_token(self, client):
         """Test getting current user with invalid token"""
         response = client.get(
-            "/api/v1/auth/me",
-            headers={"Authorization": "Bearer invalid_token_here"}
+            "/api/v1/auth/me", headers={"Authorization": "Bearer invalid_token_here"}
         )
 
         assert response.status_code == 401
@@ -201,14 +201,11 @@ class TestAuthenticationAPI:
         }
 
         expired_token = jwt.encode(
-            expired_payload,
-            auth_manager.secret_key,
-            algorithm=auth_manager.algorithm
+            expired_payload, auth_manager.secret_key, algorithm=auth_manager.algorithm
         )
 
         response = client.get(
-            "/api/v1/auth/me",
-            headers={"Authorization": f"Bearer {expired_token}"}
+            "/api/v1/auth/me", headers={"Authorization": f"Bearer {expired_token}"}
         )
 
         assert response.status_code == 401
@@ -321,4 +318,3 @@ class TestAuthManager:
         user = auth_manager.authenticate_user(db, "nonexistent", "password")
 
         assert user is None
-