Add pointer interactions where it’s easy

[j-f1]

Pointer interactions have been added to:

• the action buttons at the bottom of posts
• the menu button at the top-right corner of posts
• the X favorites/X reblogs buttons on post detail pages
• avatars on posts
• close buttons in the search tab
• HUD buttons in the media preview
• the status card controls

…but not:

• the sidebar buttons
• the “X reblogged/reply to Y” headers
• metric buttons above the profile action button
• the paging tab controllers

(because those were a bit harder)