feat: integrate print templates into settings page layout

Move Print Templates from standalone page to Settings tab for
consistent navigation. Add refined card design with horizontal
layout, gradient icons, hover states, and polished dropdown menus.

- Create PrintTemplatesSettings component for Settings integration
- Add print-templates as fourth Settings tab
- Redirect /settings/print-templates to /settings?tab=print-templates
- Design TemplateCard as clickable list item with hover animations
- Add consistent icons to all dropdown menu items

Author: kasvith