[Bug]: HUD toasts cover the bar's controls and their close button does not take the click #1149

Found during the v2.1.0 release-candidate QA on macOS 26.5 arm64 (CI build run 38252812147 of release/v2.1.0 @ 9c55596, computer-use e2e pass, results in #1131).

What happens

Toasts raised in the HUD window are drawn at the bottom-right corner of the HUD window, which is where the bar's right end is. With the horizontal bar at its default bottom-centre place they cover Record, Pause, Restart, Cancel, Open Studio, Notes, the language button, Hide and Quit. Seen with:

• "Not enough disk space to start recording (only 298 MB free)..."
• "The new recording could not start. The previous one was deleted."
• "The chosen microphone could not be identified. Recording the default input.", raised at the start of every take, which hid Pause, Restart and Cancel while it was up.

They cannot be got rid of either:

• sonner pauses a toast's timer while the pointer is over it, and the pointer is naturally on the bar, so the toast stays as long as the user is reaching for the controls under it.
• Its close button does not take the click. The HUD window is click-through except over [data-hud-interactive='true'] (the hud-overlay-cursor poll in electron/windows.ts, hit-tested in LaunchWindow.tsx), and the toaster (src/components/ui/sonner.tsx, mounted in src/App.tsx for every window) is not marked, so the click lands on the app behind the HUD.

Expected

In the HUD window, toasts sit where they never overlap the bar or a popover open above it, in both the horizontal and the vertical layout, and stay on screen; their close button takes the click.

Platform

macOS 26.5 arm64. The code path is the same on Windows (click-through HUD); Linux never makes the HUD click-through, so only the overlap applies there.