Intentional deviation from Ghostty 1.3.1 (DEVIANT_FIXES.md row 31).
Zig's apprt/gtk/ipc/new_window.zig:49-53 builds the D-Bus argument
array from raw bytes as a *trusted* GVariant; an argument with invalid
UTF-8 or an interior NUL violates GVariant's string invariants, which
GLib turns into a process abort. The Rust port mirrored this with an
explicit abort().
new_window now validates every argument before touching the bus: a bad
argument prints an error to stderr and returns Error::IpcFailed, so the
CLI exits with failure and nothing crashes. Valid arguments are sent
byte-identically to Ghostty.
Test Plan:
- cargo test -p ghostty-apprt-gtk new_window
(invalid_dbus_strings_are_rejected_without_abort)