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>

app/exceptions/vendor_theme.py

@@ -4,12 +4,9 @@ Vendor theme management specific exceptions.
 """
 
 from typing import Any, Dict, Optional
-from .base import (
-    ResourceNotFoundException,
-    ConflictException,
-    ValidationException,
-    BusinessLogicException
-)
+
+from .base import (BusinessLogicException, ConflictException,
+                   ResourceNotFoundException, ValidationException)
 
 
 class VendorThemeNotFoundException(ResourceNotFoundException):
@@ -28,10 +25,10 @@ class InvalidThemeDataException(ValidationException):
     """Raised when theme data is invalid."""
 
     def __init__(
-            self,
-            message: str = "Invalid theme data",
-            field: Optional[str] = None,
-            details: Optional[Dict[str, Any]] = None,
+        self,
+        message: str = "Invalid theme data",
+        field: Optional[str] = None,
+        details: Optional[Dict[str, Any]] = None,
     ):
         super().__init__(
             message=message,
@@ -62,10 +59,10 @@ class ThemeValidationException(ValidationException):
     """Raised when theme validation fails."""
 
     def __init__(
-            self,
-            message: str = "Theme validation failed",
-            field: Optional[str] = None,
-            validation_errors: Optional[Dict[str, str]] = None,
+        self,
+        message: str = "Theme validation failed",
+        field: Optional[str] = None,
+        validation_errors: Optional[Dict[str, str]] = None,
     ):
         details = {}
         if validation_errors:
@@ -86,10 +83,7 @@ class ThemePresetAlreadyAppliedException(BusinessLogicException):
         super().__init__(
             message=f"Preset '{preset_name}' is already applied to vendor '{vendor_code}'",
             error_code="THEME_PRESET_ALREADY_APPLIED",
-            details={
-                "preset_name": preset_name,
-                "vendor_code": vendor_code
-            },
+            details={"preset_name": preset_name, "vendor_code": vendor_code},
         )
 
 
@@ -120,18 +114,13 @@ class InvalidFontFamilyException(ValidationException):
 class ThemeOperationException(BusinessLogicException):
     """Raised when theme operation fails."""
 
-    def __init__(
-            self,
-            operation: str,
-            vendor_code: str,
-            reason: str
-    ):
+    def __init__(self, operation: str, vendor_code: str, reason: str):
         super().__init__(
             message=f"Theme operation '{operation}' failed for vendor '{vendor_code}': {reason}",
             error_code="THEME_OPERATION_FAILED",
             details={
                 "operation": operation,
                 "vendor_code": vendor_code,
-                "reason": reason
+                "reason": reason,
             },
         )