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>

app/exceptions/admin.py

@@ -3,10 +3,14 @@
 Admin operations specific exceptions.
 """
 
-from typing import Any, Dict, Optional
+from typing import Any
 
-from .base import (AuthorizationException, BusinessLogicException,
-                   ResourceNotFoundException, ValidationException)
+from .base import (
+    AuthorizationException,
+    BusinessLogicException,
+    ResourceNotFoundException,
+    ValidationException,
+)
 
 
 class UserNotFoundException(ResourceNotFoundException):
@@ -36,7 +40,7 @@ class UserStatusChangeException(BusinessLogicException):
         user_id: int,
         current_status: str,
         attempted_action: str,
-        reason: Optional[str] = None,
+        reason: str | None = None,
     ):
         message = f"Cannot {attempted_action} user {user_id} (current status: {current_status})"
         if reason:
@@ -61,7 +65,7 @@ class ShopVerificationException(BusinessLogicException):
         self,
         shop_id: int,
         reason: str,
-        current_verification_status: Optional[bool] = None,
+        current_verification_status: bool | None = None,
     ):
         details = {
             "shop_id": shop_id,
@@ -85,8 +89,8 @@ class AdminOperationException(BusinessLogicException):
         self,
         operation: str,
         reason: str,
-        target_type: Optional[str] = None,
-        target_id: Optional[str] = None,
+        target_type: str | None = None,
+        target_id: str | None = None,
     ):
         message = f"Admin operation '{operation}' failed: {reason}"
 
@@ -142,7 +146,7 @@ class InvalidAdminActionException(ValidationException):
         self,
         action: str,
         reason: str,
-        valid_actions: Optional[list] = None,
+        valid_actions: list | None = None,
     ):
         details = {
             "action": action,
@@ -167,7 +171,7 @@ class BulkOperationException(BusinessLogicException):
         operation: str,
         total_items: int,
         failed_items: int,
-        errors: Optional[Dict[str, Any]] = None,
+        errors: dict[str, Any] | None = None,
     ):
         message = f"Bulk {operation} completed with errors: {failed_items}/{total_items} failed"
 
@@ -194,7 +198,7 @@ class ConfirmationRequiredException(BusinessLogicException):
     def __init__(
         self,
         operation: str,
-        message: Optional[str] = None,
+        message: str | None = None,
         confirmation_param: str = "confirm",
     ):
         if not message:
@@ -217,7 +221,7 @@ class VendorVerificationException(BusinessLogicException):
         self,
         vendor_id: int,
         reason: str,
-        current_verification_status: Optional[bool] = None,
+        current_verification_status: bool | None = None,
     ):
         details = {
             "vendor_id": vendor_id,