Add Support for Loop WM

[plyght]

Problem Description

Window Reversion After Manual Loop Adjustment
When using Loop’s radial menu (with mouse/arrow keys) to manually reposition a window over another:

1. Moved window overlaps target window (no swap occurs).
2. Switching focus to another window/app triggers Amethyst to revert the moved window to its original pre-Loop position.
3. Expected behavior: Amethyst should treat the Loop-adjusted position as intentional and swap windows instead of restoring old layouts.

Root Cause Analysis

• Amethyst’s layout engine periodically reasserts its tiling logic (e.g., on focus changes), overriding manual Loop adjustments.
• Loop’s movement logic does not update Amethyst’s internal state, causing a "layout drift" that Amethyst "corrects" aggressively.

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Requested Solution

1. Manual Window Position Locking

• Add a lock_window_positions: bool config option to pause layout reassertion for manually moved windows.
• Integrate with macOS’s AXUIElementSetAttributeValue to flag windows moved via external tools.

2. Swapping Instead of Reversion

• When Amethyst detects a window was manually moved over another:
  • Swap their positions in the layout grid (if compatible with active layout).
  • Resize both windows to fit the layout (e.g., halves, thirds).

3. Loop-Specific Integration

• Expose a Swift/AppleScript API for Loop to notify Amethyst of manual moves:

  AmethystBridge.shared.notifyWindowMoved(windowID: CGWindowID, newFrame: CGRect)  

• Add Amethyst config to trust Loop-sourced movements:

  experimental:  
    accept_external_window_events:  
      - com.MrKai77.Loop  

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Alternatives Tested & Rejected

• Yabai’s window_placement=second_child: Works for swaps but lacks Loop’s radial UX.
• Amethyst’s mouse_follows_focus: No impact on layout reversion behavior.
• Disabling Amethyst temporarily: Defeats the purpose of hybrid tiling.

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Additional Context

• Reproduction Steps:

  1. Open two windows in Amethyst (Tall layout).
  2. Use Loop’s radial menu to move Window A over Window B.
  3. Click Window C (or another app).
  4. Observe: Window A snaps back, overlap persists.

• Technical Constraints:

  • Loop cannot inject NSEvent to mimic Amethyst-native resize commands.
  • Amethyst’s WindowManager does not account for external frame changes unless triggered via its own logic.

• Proposed Architecture:

  Loop Movement → AX API → Amethyst Observer → Layout Recalculation → Swap/Resize