feat: #3632629 Add a Pill display for taxonomy terms

Adds a Pills display to the taxonomy block, rendering topic links as rounded, wrapping pills without requiring D3. It preserves access filtering, translated labels, term limits, direct links for singly used terms, and More tags. Scoped list styles leave administrative contextual controls intact.

Issue: #3632629

Validation

1 functional test passed with 45 assertions. Drupal/DrupalPractice coding standards and whitespace checks passed.