feat(wm): add tiling and floating ws layers

This commit introduces an implementation of workspace layers to
komorebi.

Workspace layers change the kinds of windows that certain commands
operate on. This implementation features two variants,
WorkspaceLayer::Tiling and WorkspaceLayer::Floating.

The default behaviour until now has been WorkspaceLayer::Tiling.

When the user sets WorkspaceLayer::Floating, either through the
'toggle-workspace-layer' command or the new bar widget, the 'move',
'focus', 'cycle-focus' and 'resize-axis' commands will operate on
floating windows, if the currently focused window is a floating window.

As I don't have 'cycle-focus' bound to anything, 'focus up' and 'focus
down' double as incrementing and decrementing cycle focus commands,
iterating focus through the floating windows assigned to a workspace.

Floating windows in komorebi belong to specific workspaces, therefore
commands such as 'move' and 'resize-axis' will restrict movement and
resizing to the bounds of their workspace's work area (or more
accurately, the work area of the monitor that the workspace belongs to,
as floating windows are never constrained by workspace-specific work
area restrictions).

komorebic/src/main.rs

@@ -1269,6 +1269,8 @@ enum SubCommand {
     /// mode, for the currently focused workspace. If there was no override value set for the
     /// workspace previously it takes the opposite of the global value.
     ToggleWorkspaceFloatOverride,
+    /// Toggle between the Tiling and Floating layers on the focused workspace
+    ToggleWorkspaceLayer,
     /// Toggle window tiling on the focused workspace
     TogglePause,
     /// Toggle window tiling on the focused workspace
@@ -2854,6 +2856,9 @@ if (Get-Command Get-CimInstance -ErrorAction SilentlyContinue) {
         SubCommand::ToggleWorkspaceFloatOverride => {
             send_message(&SocketMessage::ToggleWorkspaceFloatOverride)?;
         }
+        SubCommand::ToggleWorkspaceLayer => {
+            send_message(&SocketMessage::ToggleWorkspaceLayer)?;
+        }
         SubCommand::WindowHidingBehaviour(arg) => {
             send_message(&SocketMessage::WindowHidingBehaviour(arg.hiding_behaviour))?;
         }