refactor(ring): stop exposing Ring internals

[JustForFun88]

Summary

This PR hides the internals of the Ring<T> type and reworks its API. Direct access to the internal VecDeque<T> is removed, so interaction with Ring now happens only through its methods, making it easier and safer to use.

All lock-respecting insert/remove/swap logic is implemented directly on Ring and the separate LockableSequence trait removed.

The new API is more ergonomic and expressive for common patterns. As a result, although many new methods were added to Ring in komorebi/src/ring.rs, the total code size increased only slightly, since many typical iterator chains are now replaced by single method calls.

Motivation

• Prevents accidental misuse by hiding internal collections and providing a clear, uniform API.
• Enables future refactoring or switching to another implementation without breaking external code.

Usability Improvements

• Consistent Access: Field and accessor now always return Ring, eliminating confusion between types (e.g., &monitor.workspaces vs monitor.workspaces()).

  // Before: different types, easy to misuse
  &monitor.workspaces     // &Ring<Workspace>
  monitor.workspaces()    // &VecDeque<Workspace>
  
  // After: always &Ring<Workspace>
  &monitor.workspaces
  monitor.workspaces()

• Ergonomic usage: The new API is more ergonomic and expressive for common patterns

  monitors.indexed()            // replaces monitors.elements().iter().enumerate()
  monitors.position(..)         // replaces monitors.elements().iter().position(..)
  ws.floating_windows().any(..) // replaces ws.floating_windows().iter().any(..)

Tests

Tested on Windows 11.