Create EmailTemplateService to follow layered architecture: - Move database queries from API endpoints to service - Move business logic (validation, resolution) to service - Reduce architecture violations from 62 to 29 errors Files: - app/services/email_template_service.py (new) - app/api/v1/admin/email_templates.py (refactored) - app/api/v1/vendor/email_templates.py (refactored) 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>