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>

models/schema/vendor_domain.py

@@ -12,7 +12,6 @@ Schemas include:
 
 import re
 from datetime import datetime
-from typing import Dict, List, Optional
 
 from pydantic import BaseModel, ConfigDict, Field, field_validator
 
@@ -69,8 +68,8 @@ class VendorDomainCreate(BaseModel):
 class VendorDomainUpdate(BaseModel):
     """Schema for updating vendor domain settings."""
 
-    is_primary: Optional[bool] = Field(None, description="Set as primary domain")
-    is_active: Optional[bool] = Field(None, description="Activate or deactivate domain")
+    is_primary: bool | None = Field(None, description="Set as primary domain")
+    is_active: bool | None = Field(None, description="Activate or deactivate domain")
 
     model_config = ConfigDict(from_attributes=True)
 
@@ -87,9 +86,9 @@ class VendorDomainResponse(BaseModel):
     is_active: bool
     is_verified: bool
     ssl_status: str
-    verification_token: Optional[str] = None
-    verified_at: Optional[datetime] = None
-    ssl_verified_at: Optional[datetime] = None
+    verification_token: str | None = None
+    verified_at: datetime | None = None
+    ssl_verified_at: datetime | None = None
     created_at: datetime
     updated_at: datetime
 
@@ -97,7 +96,7 @@ class VendorDomainResponse(BaseModel):
 class VendorDomainListResponse(BaseModel):
     """Schema for paginated vendor domain list."""
 
-    domains: List[VendorDomainResponse]
+    domains: list[VendorDomainResponse]
     total: int
 
 
@@ -106,9 +105,9 @@ class DomainVerificationInstructions(BaseModel):
 
     domain: str
     verification_token: str
-    instructions: Dict[str, str]
-    txt_record: Dict[str, str]
-    common_registrars: Dict[str, str]
+    instructions: dict[str, str]
+    txt_record: dict[str, str]
+    common_registrars: dict[str, str]
 
     model_config = ConfigDict(from_attributes=True)