- Add field mapping properties to NotificationTemplatesConfig interface for unlock, favorite, message, and daily recommend templates
- Add UI form fields in system config view for configuring JSON-based field mappings with helper text
- Implement dynamic template data construction using configured field mappings in NotificationService
- Add fallback to traditional first/keyword format when field mapping is not configured
- Support flexible field mapping with value types: title, name, content, time, remark
- Update SystemConfigService to persist and retrieve field mapping configurations
- Enable backend-driven template field customization without code changes
