feat(scripts): add off-screen launch capture, layout/size, and tests to screenshot.py

Extends screenshot.py with --launch CMD, which runs a command on a transient headless Hyprland output, captures it, and tears the output down, so a UI can be verified without touching the visible workspace. --layout (tiled/monocle/floating) and --size control placement: output resolution for tiled/monocle, window size plus centering for floating.

Refactors the testable logic (size parsing, geometry strings, window matching, the exec-rule body, centering) into pure helpers and adds test_screenshot.py covering them across normal, boundary, and error cases. The grim/hyprctl wrappers and the capture orchestration stay thin and are verified functionally.

0 files changed, 0 insertions, 0 deletions