Improve cache clearing/GC/heap dump behavior

[labkey-jeckels]

Rationale

We should switch cache clearing and heap dumping from GET to POST, and we can do more specific permission checks on a few actions.

Changes

• Move cache clearing and garbage collecting to an API
• Add a confirmation on heap dumping
• Use DOM builder for cache listings
• Generics and other lint cleanup

Tasks 📍

• Manual Testing
  • Verify caches page continues to render
  • Verify that cache clearing, GC, and heap dumping UI still works from Admin Console
• Test Automation