refactor: modernize code quality tooling with Ruff

- Replace black, isort, and flake8 with Ruff (all-in-one linter and formatter)
- Add comprehensive pyproject.toml configuration
- Simplify Makefile code quality targets
- Configure exclusions for venv/.venv in pyproject.toml
- Auto-fix 1,359 linting issues across codebase

Benefits:
- Much faster builds (Ruff is written in Rust)
- Single tool replaces multiple tools
- More comprehensive rule set (UP, B, C4, SIM, PIE, RET, Q)
- All configuration centralized in pyproject.toml
- Better import sorting and formatting consistency

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

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

scripts/init_production.py

@@ -17,7 +17,7 @@ This script is idempotent - safe to run multiple times.
 """
 
 import sys
-from datetime import datetime, timezone
+from datetime import UTC, datetime
 from pathlib import Path
 
 # Add project root to path
@@ -27,10 +27,13 @@ sys.path.insert(0, str(project_root))
 from sqlalchemy import select
 from sqlalchemy.orm import Session
 
-from app.core.config import (print_environment_info, settings,
-                             validate_production_settings)
+from app.core.config import (
+    print_environment_info,
+    settings,
+    validate_production_settings,
+)
 from app.core.database import SessionLocal
-from app.core.environment import get_environment, is_production
+from app.core.environment import is_production
 from app.core.permissions import PermissionGroups
 from middleware.auth import AuthManager
 from models.database.admin import AdminSetting
@@ -97,8 +100,8 @@ def create_admin_user(db: Session, auth_manager: AuthManager) -> User:
         last_name=settings.admin_last_name,
         is_active=True,
         is_email_verified=True,
-        created_at=datetime.now(timezone.utc),
-        updated_at=datetime.now(timezone.utc),
+        created_at=datetime.now(UTC),
+        updated_at=datetime.now(UTC),
     )
 
     db.add(admin)
@@ -218,8 +221,8 @@ def create_admin_settings(db: Session) -> int:
                 value_type=setting_data["value_type"],
                 description=setting_data.get("description"),
                 is_public=setting_data.get("is_public", False),
-                created_at=datetime.now(timezone.utc),
-                updated_at=datetime.now(timezone.utc),
+                created_at=datetime.now(UTC),
+                updated_at=datetime.now(UTC),
             )
             db.add(setting)
             settings_created += 1
@@ -320,14 +323,14 @@ def print_summary(db: Session):
     user_count = db.query(User).filter(User.role == "admin").count()
     setting_count = db.query(AdminSetting).count()
 
-    print(f"\n📊 Database Status:")
+    print("\n📊 Database Status:")
     print(f"  Admin users:     {user_count}")
     print(f"  Admin settings:  {setting_count}")
 
     print("\n" + "─" * 70)
     print("🔐 ADMIN CREDENTIALS")
     print("─" * 70)
-    print(f"  URL:      /admin/login")
+    print("  URL:      /admin/login")
     print(f"  Username: {settings.admin_username}")
     print(f"  Password: {settings.admin_password}")
     print("─" * 70)