- Issue #1: Category show page now lists published posts in that category
- Issue #2: Admin panel at /admin with posts and categories management tables;
  publish/unpublish buttons on posts table; Admin nav link
- Issue #3: Comments section on post show page with author/date display
  and submit-comment form; comments load approved-only on publish

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>