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>

models/schema/vendor_domain.py

@@ -12,7 +12,8 @@ Schemas include:
 
 import re
 from datetime import datetime
-from typing import List, Optional, Dict
+from typing import Dict, List, Optional
+
 from pydantic import BaseModel, ConfigDict, Field, field_validator
 
 
@@ -23,14 +24,13 @@ class VendorDomainCreate(BaseModel):
         ...,
         description="Custom domain (e.g., myshop.com or shop.mybrand.com)",
         min_length=3,
-        max_length=255
+        max_length=255,
     )
     is_primary: bool = Field(
-        default=False,
-        description="Set as primary domain for the vendor"
+        default=False, description="Set as primary domain for the vendor"
     )
 
-    @field_validator('domain')
+    @field_validator("domain")
     @classmethod
     def validate_domain(cls, v: str) -> str:
         """Validate and normalize domain."""
@@ -44,20 +44,22 @@ class VendorDomainCreate(BaseModel):
         domain = domain.lower().strip()
 
         # Basic validation
-        if not domain or '/' in domain:
+        if not domain or "/" in domain:
             raise ValueError("Invalid domain format")
 
-        if '.' not in domain:
+        if "." not in domain:
             raise ValueError("Domain must have at least one dot")
 
         # Check for reserved subdomains
-        reserved = ['www', 'admin', 'api', 'mail', 'smtp', 'ftp', 'cpanel', 'webmail']
-        first_part = domain.split('.')[0]
+        reserved = ["www", "admin", "api", "mail", "smtp", "ftp", "cpanel", "webmail"]
+        first_part = domain.split(".")[0]
         if first_part in reserved:
-            raise ValueError(f"Domain cannot start with reserved subdomain: {first_part}")
+            raise ValueError(
+                f"Domain cannot start with reserved subdomain: {first_part}"
+            )
 
         # Validate domain format (basic regex)
-        domain_pattern = r'^[a-z0-9]([a-z0-9-]{0,61}[a-z0-9])?(\.[a-z0-9]([a-z0-9-]{0,61}[a-z0-9])?)*$'
+        domain_pattern = r"^[a-z0-9]([a-z0-9-]{0,61}[a-z0-9])?(\.[a-z0-9]([a-z0-9-]{0,61}[a-z0-9])?)*$"
         if not re.match(domain_pattern, domain):
             raise ValueError("Invalid domain format")
 
@@ -75,6 +77,7 @@ class VendorDomainUpdate(BaseModel):
 
 class VendorDomainResponse(BaseModel):
     """Standard schema for vendor domain response."""
+
     model_config = ConfigDict(from_attributes=True)
 
     id: int