c8b37c8d2e
Upstream Pi's deleteKittyImage/deleteAllKittyImages return unwrapped control sequences; legacy callers such as pi-sprite wrap tmux passthrough themselves. Aliasing OMP's auto-wrapping encodeKittyDeleteImage (and hand-wrapping deleteAllKittyImages) double-wrapped under tmux, so the outer terminal dropped the delete command. Match the upstream bare-sequence contract and pin it in the regression test.