[Bug/Feature]: Enable area selection overlay to cover the macOS Menubar

[dennyschroeder]

Hi @richiemcilroy,

Currently, when triggering the Area Screenshot tool, the top macOS Menubar gets grayed out and is excluded from the selectable area bounds.

Problem:
When reporting software bugs or giving product feedback, I frequently need to capture open application menus, system clock timestamps, or status items located directly inside the Menubar.

Proposed Solution:
Please allow the selection crosshair and overlay to cover 100% of the screen geometry, including the native macOS Menubar area, without dimming it out.

[linear]

CAP-714

[tembo]

Looking at the codebase, this involves how the target selection overlay window is positioned on macOS.

The overlay window bounds are set in apps/desktop/src-tauri/src/windows.rs at lines 1556-1564:

let position = display.raw_handle().logical_position();
let size = display.logical_size().unwrap();

window_builder = window_builder
    .inner_size(size.width(), size.height())
    .position(position.x(), position.y());

These values come from CGDisplayBounds in crates/scap-targets/src/platform/macos.rs (lines 53-68), which returns the display's bounds in points. However, macOS has a concept of "visible frame" vs "frame" - the visible frame excludes the menubar area, while the full frame includes it.

The fix would involve using the full display frame instead of the visible frame when setting up the overlay window. On macOS, this typically means using NSScreen.frame rather than relying solely on CGDisplayBounds, or explicitly positioning the window to start at y=0 (top of screen) with a height that includes the menubar.

Key files to modify:

• crates/scap-targets/src/platform/macos.rs - potentially add a method that returns the full screen frame including menubar
• apps/desktop/src-tauri/src/windows.rs - update ShowCapWindow::TargetSelectOverlay to use full screen bounds

One consideration: the overlay needs to handle the fact that the menubar can be on different edges depending on screen arrangement, and the primary display's menubar height may differ from other displays.