chatterbox-fast v0.1.0

Sub-second streaming TTS on Chatterbox-Turbo via adaptive buffer-ratchet
chunking. First audio in ~0.5s (vs ~5s one-shot) with no quality compromise —
chunk joins land on natural sentence pauses and the stream converges to one
large near-full-context chunk within 2-3 joins. Works because the engine runs
faster than realtime; the no-starvation guarantee is proven in a GPU-free
simulation (tests/test_scheduler.py).

- chatterbox_fast/scheduler.py: the adaptive-chunk scheduler (pure logic, no GPU)
- chatterbox_fast/app.py: FastAPI server (POST /tts streaming, /voices, /health)
- bench.py: streaming client (ground-truth TTFB + starvation check)
- Self-contained Dockerfile (slim base + chatterbox-tts from PyPI)
- Three public-domain LibriVox starter voices baked in (see voices/ATTRIBUTION.md)

MIT licensed.

voices/ATTRIBUTION.md

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+# Starter voice attribution
+
+The voices shipped with chatterbox-fast are short clips from **LibriVox**, whose
+recordings are dedicated to the **public domain** in the USA
+(<https://librivox.org/pages/public-domain/>). No attribution is legally required;
+it's provided here out of respect for the volunteer readers.
+
+All three are excerpts from *LibriVox Short Poetry Collection 001*
+(<https://archive.org/details/short_poetry_001_librivox>):
+
+| voice | reader | from |
+|---|---|---|
+| `catharine` | Catharine Eastman | "Dover Beach" — Matthew Arnold |
+| `peter` | Peter Yearsley | "Lament of the Irish Emigrant" — Lady Dufferin (H. Selina) |
+| `kara` | Kara Shallenberg | "How They Brought the Good News from Ghent to Aix" — Robert Browning |
+
+Each is a ~20-second mono excerpt, used as a voice-cloning reference. The underlying
+poems are themselves in the public domain.

voices/README.md

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+# voices
+
+Each `*.wav` in this directory is a predefined voice. The file **stem** becomes
+the voice name returned by `GET /voices` and selectable via the `voice` request
+field. The server clones the reference on the fly — no training, no enrollment.
+
+**A good reference clip is:** 5–30 seconds, a single speaker, clean (minimal
+noise/music), 16 kHz or higher, mono. Match the clip's language to your text.
+
+Add a voice by dropping a wav in here (or mounting your own directory at
+`CBF_VOICES_DIR`); `/voices` re-scans on every call, so no restart is needed.
+
+## Licensing note
+
+The voices shipped in this open-source repository are **redistributable** (public
+domain / explicitly licensed for redistribution). If you add your own voices,
+make sure you have the right to use — and, if you redistribute the image, to
+share — those clips. Don't ship voices of real people or copyrighted characters
+without permission.