Add sortable date columns to topics index

[LucassF5]

What Issue Does This PR Cover, If Any?

Resolves #699

What Changed? And Why Did It Change?

• Replaced the unused Description column in the Topics list with an Added date column based on created_at.
• Added a Published column before Title and removed the published date from the title cell.
• Removed the UID column from the Topics list.
• Added clickable sorting headers for Published and Added while preserving existing filters.
• Left the description field in the Topics edit form unchanged.
• Kept this as a UI-only change with no schema updates.

How Has This Been Tested?

• bin/rspec spec/requests/topics/index_spec.rb
• bin/rails tailwindcss:build
• RUBOCOP_CACHE_ROOT=tmp/rubocop_cache bin/rubocop app/controllers/topics_controller.rb app/helpers/topics_helper.rb spec/requests/topics/index_spec.rb

Please Provide Screenshots

Not included.

Additional Comments

The implementation keeps the default Topics ordering by published date descending and only switches to the Added date when the created_at sort is selected.