Fix quadratic Wyoming audio buffering

[basnijholt]

Summary

• accumulate Wyoming PCM chunks in a mutable bytearray to avoid copying the complete recording for every chunk
• convert buffered audio to bytes once when recording stops, then reuse the buffer
• add a regression test that verifies chunk accumulation stays in place
• pin the Ruff pre-commit hook to the project's 0.15 lint baseline; 0.16 activates repo-wide findings and breaks pre-commit.ci

Testing

• uv run --all-extras pytest (1477 passed, 4 skipped)
• uv run ruff check .
• uv run pre-commit run --all-files

[greptile-apps]

Greptile Summary

The PR replaces repeated immutable PCM concatenation with in-place bytearray accumulation, converting the buffer to bytes once before WAV creation. It also adds a focused regression test and aligns the pre-commit Ruff hook with the project’s 0.15 tooling baseline.

• Accumulates converted Wyoming audio chunks without repeatedly copying the complete recording.
• Preserves the existing WAV and transcription interfaces by converting the completed buffer to bytes.
• Verifies that multiple chunks retain the same mutable buffer.
• Pins the pre-commit Ruff hook to v0.15.22.

Confidence Score: 5/5

The PR appears safe to merge.

No blocking failure remains.

Important Files Changed

Filename	Overview
agent_cli/server/whisper/wyoming_handler.py	Replaces quadratic bytes concatenation with bytearray extension while preserving stop-path audio contents and lifecycle behavior.
tests/test_server_whisper_wyoming.py	Adds a regression test confirming that successive audio chunks accumulate in the same buffer.
.pre-commit-config.yaml	Pins ruff-pre-commit to v0.15.22 to align with the repository’s Ruff 0.15 baseline.

_{Reviews (2): Last reviewed commit: "ci: pin Ruff hook to project baseline" | Re-trigger Greptile}