Modernize Tags Portlet

[fmontes]

This epic covers the full modernization of the Tags portlet, replacing the legacy UI with Angular and ensuring consistent, and REST APIs to manage tags. The goal is to improve usability, performance, and maintainability while preserving existing functionality.

Special Considerations:

• Must support pagination, filtering, and sorting in the listing view.
• Tag name must be unique; validation required both client-side and server-side.
• Must support batch operations and import/export from CSV or JSON formats.
• Tags can be global or tied to a specific site — the API and UI must respect this scope.
• Existing APIs are partially implemented but inconsistent; some must be refactored or replaced.
• Minimal changes to tagging model — focus is on UX, performance, and maintainability.

Links:

• API Spec
• Designs (WIP)

[github-actions]

PRs linked to this issue

• feat(menu): Add new Angular Tags portlet to /api/v1/menu and admin sidebar by @hmoreras