Position window actions over the actual window

[SQReder]

Context

The window actions bar (split / stack / pull up / float / more) is laid out from the node's ComputedRectangle, i.e. the layout cell, while the reveal logic in TilingWindowViewModel hit-tests the cursor against the real window position.

The two only agree while the window fills its cell. A window that is smaller than its cell — for example one that has reached its maximum size, which ends up left-aligned in the cell — gets the bar centered over the cell, outside the horizontal range that keeps the bar visible. Moving the cursor towards the bar hides it, so the actions are unreachable for such windows.

Changes

• Add TilingWindowViewModel.ActionsBounds: the visible window bounds (position minus frame margins) in overlay coordinates, refreshed in the same cursor handler that decides whether the bar is shown.
• Bind the actions bar container and the reveal highlight to ActionsBounds instead of ComputedBounds. The focus/preview rectangles still use the cell.

Verification

• dotnet build FancyWM.GUI (Debug) — 0 errors.
• Manual: a 755 px wide browser popup tiled into a 1431 px wide cell. Before: the bar appears over the middle of the cell and vanishes when approached. After: the bar appears centered over the window and its buttons are clickable.
• Unit tests were not run locally.

Risks

• ActionsBounds is only refreshed on cursor movement, so it holds a stale value while the bar is hidden. It is refreshed before the bar can be revealed.
• Touches the same method as the "close the more-options menu" PR; whichever lands second will need a trivial rebase.

🤖 Generated with Claude Code

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