Felt Orbit ORHACK demo v13 - fixed known sample length

Deep comparison result:
- The bundled WAV itself is intact: 217,956 stereo frames, 44.1 kHz, 4.9423129 s.
- v10 can sound, but the voice still obtains playback length from soundfile_info.
- For this dedicated one-sample instrument that indirection is unnecessary.

This build is based on v10 (NO LATCH, known to sound).
Pitch/octave is untouched.
No release experiment.
Only playback-length handling changed:
- soundfile_info no longer writes $0-samplesize
- loadbang sets $0-samplesize directly to 217956 frames

This tests whether the fixed relative filename was giving the Samplemento
metadata path a wrong/partial duration even though readsf~ could play the file.
