Screenshot soak test

The default Rust test suite uses a fake capturer and never requests macOS Screen Recording permission. To exercise a real Zeus window deliberately, run this from zeus/ while the Zeus app has an open window:

ZEUS_SCREENSHOT_SOAK=1 cargo test -p zeus-engine real_window_soak_is_explicitly_opt_in

macOS may ask for Screen Recording permission for Zeus. The test captures one 720p JPEG in memory, stops the stream immediately, and writes no screenshot file, so there is no artifact cleanup. Remove Zeus under System Settings → Privacy & Security → Screen Recording if you also want to clear the grant.