[Bug]: SnapShot animation leaves an oversized bar on Hyprland

Before submitting

• I searched existing issues and did not find a duplicate.
• I included enough detail to reproduce or investigate the problem.

Area

apps/desktop

Steps to reproduce

1. On Omarchy / Hyprland 0.56.2, enable SnapShots and Capture animations in the desktop app.
2. Capture another app on the same monitor as T3 Code.
3. Repeat with the captured app on another monitor.
4. Watch the screenshot shrink into the composer before the animation overlay disappears.

Expected behavior

The overlay shrinks to the attachment bounds without drawing outside the thumbnail.

Actual behavior

The thumbnail shrinks, but an oversized solid rectangle remains behind it until the overlay is removed. On the same monitor it can be wide; across monitors it can become a narrow vertical strip. The reported bar is black. A synthetic checkerboard with a white border reproduces a white rectangle, so the color depends on the image.

The finished attachment is correct. This affects the temporary animation only.

Impact

Cosmetic issue

Version or commit

Introduced with #8103. Reproduced with the installed Nightly helper and a helper built from main at 8588d7f63.

Environment

Omarchy 4 development branch, Hyprland 0.56.2, native Wayland. Two 1920x1080 monitors at scale 1.

Investigation

The helper updates the viewport size without reattaching its unchanged image buffer. Hyprland 0.56.2 copies the surface size only on a buffer update, leaving the previous dimensions around the newly scaled image. Reattaching the same buffer during resizing removes the artifact in both same-monitor and cross-monitor replay tests.

Workaround

Turn off Capture animations in Settings > SnapShots.

Work in apps/desktop, starting with the SnapShots and Capture animations entry point and the helper's viewport-resize path. Reproduce the animation on the same and another monitor, then verify the overlay no longer leaves an oversized rectangle and that the finished attachment remains correct.