[theomonnom]

TL;DR: Add exact-PCM and repeated-close regression tests for native audio receive batching.

• CPU impact: 0% production runtime change; this PR only adds tests.
• More voice sessions per core/machine: 0 directly. These tests help validate the optimization PRs; they do not add capacity themselves.

---

Add integration tests for the native receive batching change through the public Python RTC API. The tests load the actual FFI selected by LIVEKIT_LIB_PATH and pass against both stock and patched libraries; this PR changes no Python RTC production code.

Twelve combinations check exact PCM order and frame metadata at 8/24/48 kHz, mono/stereo, and 7/10/20/50 ms requested frames. A repeated-close test verifies that the stream task finishes and FFI subscriptions return to baseline over 20 iterations. Sources, tracks, streams, and collection tasks are explicitly closed/disposed.

Validation: all 13 cases passed against stock and final patched FFI, including a fresh run from this branch. The 31 existing RTC lifecycle/queue tests also passed during the accompanying investigation. Changed-file Ruff lint/format checks passed.

To exercise an alternate native library:

LIVEKIT_LIB_PATH=/absolute/path/to/liblivekit_ffi.so \
  python -m pytest livekit-rtc/tests/test_audio_native_batching.py -q -o asyncio_mode=auto

These local-source checks do not need an SFU. They cover exact sample delivery and cleanup, not network jitter, acoustic interruption latency, or production session capacity.

Related draft PRs: receive batching, Opus AVX2, Python log filtering, inline VAD.

[github-actions]

👋 This PR has no changeset. If it should be released, add a markdown file under .changeset/ (any name, e.g. .changeset/fix-token-parsing.md):

---
"livekit-rtc": patch
---

Short description of the change, used in the release notes.

• Packages: livekit-rtc, livekit-api, livekit-protocol (one line per package)
• Types: patch, minor, major, patch-rc, minor-rc, major-rc, next-rc, promote

If this change doesn't need a release (docs, CI, tests), you can ignore this comment.