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/customer.py

@@ -4,13 +4,10 @@ Customer management specific exceptions.
 """
 
 from typing import Any, Dict, Optional
-from .base import (
-    ResourceNotFoundException,
-    ConflictException,
-    ValidationException,
-    AuthenticationException,
-    BusinessLogicException
-)
+
+from .base import (AuthenticationException, BusinessLogicException,
+                   ConflictException, ResourceNotFoundException,
+                   ValidationException)
 
 
 class CustomerNotFoundException(ResourceNotFoundException):
@@ -21,7 +18,7 @@ class CustomerNotFoundException(ResourceNotFoundException):
             resource_type="Customer",
             identifier=customer_identifier,
             message=f"Customer '{customer_identifier}' not found",
-            error_code="CUSTOMER_NOT_FOUND"
+            error_code="CUSTOMER_NOT_FOUND",
         )
 
 
@@ -32,7 +29,7 @@ class CustomerAlreadyExistsException(ConflictException):
         super().__init__(
             message=f"Customer with email '{email}' already exists",
             error_code="CUSTOMER_ALREADY_EXISTS",
-            details={"email": email}
+            details={"email": email},
         )
 
 
@@ -43,10 +40,7 @@ class DuplicateCustomerEmailException(ConflictException):
         super().__init__(
             message=f"Email '{email}' is already registered for this vendor",
             error_code="DUPLICATE_CUSTOMER_EMAIL",
-            details={
-                "email": email,
-                "vendor_code": vendor_code
-            }
+            details={"email": email, "vendor_code": vendor_code},
         )
 
 
@@ -57,7 +51,7 @@ class CustomerNotActiveException(BusinessLogicException):
         super().__init__(
             message=f"Customer account '{email}' is not active",
             error_code="CUSTOMER_NOT_ACTIVE",
-            details={"email": email}
+            details={"email": email},
         )
 
 
@@ -67,7 +61,7 @@ class InvalidCustomerCredentialsException(AuthenticationException):
     def __init__(self):
         super().__init__(
             message="Invalid email or password",
-            error_code="INVALID_CUSTOMER_CREDENTIALS"
+            error_code="INVALID_CUSTOMER_CREDENTIALS",
         )
 
 
@@ -78,13 +72,9 @@ class CustomerValidationException(ValidationException):
         self,
         message: str = "Customer validation failed",
         field: Optional[str] = None,
-        details: Optional[Dict[str, Any]] = None
+        details: Optional[Dict[str, Any]] = None,
     ):
-        super().__init__(
-            message=message,
-            field=field,
-            details=details
-        )
+        super().__init__(message=message, field=field, details=details)
         self.error_code = "CUSTOMER_VALIDATION_FAILED"
 
 
@@ -95,8 +85,5 @@ class CustomerAuthorizationException(BusinessLogicException):
         super().__init__(
             message=f"Customer '{customer_email}' not authorized for: {operation}",
             error_code="CUSTOMER_NOT_AUTHORIZED",
-            details={
-                "customer_email": customer_email,
-                "operation": operation
-            }
+            details={"customer_email": customer_email, "operation": operation},
         )