Add AuK voice-editing demo

Edits emotion on an existing recording in place (same speaker, words,
duration) rather than steering style at generation time. Demo runs
"Change the emotion to excited." on the public-domain narrator clip
already used by whisperx/tts.

Found and documented three real environment/packaging gaps on the RTX
3090: a missing audioread dependency, a huggingface_hub/transformers
version conflict from installing the hf CLI, and --cpu_offload being
mandatory (not optional) since AuK's own undoffloaded VRAM figures
exceed 24GB entirely. Also found the practical input-length ceiling is
~25-30s, not the several minutes a podcast episode would need — an 80s
clip OOM'd on attention memory even with offload enabled.

Co-Authored-By: Claude Sonnet 5 <[email protected]>
Claude-Session: https://claude.ai/code/session_01Y1oQ4h4WE4R9KRvMQLr5Ey

README.md

@@ -6,7 +6,9 @@ Audio processing demos: WhisperX, Demucs, and TTS technology proofs-of-concept.
 
 - `whisperx/` — speech-to-text with word-level alignment and diarization
 - `demucs/` — source separation (vocals/instrumentals stem splitting)
-- `tts/` — text-to-speech service demos
+- `tts/` — text-to-speech service demos (voice cloning via MOSS-TTS)
+- `auk/` — voice *editing* demos (emotion/pitch/speed/content editing on existing recordings,
+  as opposed to `tts/`'s clone-and-generate approach)
 
 Each subdirectory has its own README with setup and run instructions.