feat: Add audio direction estimator (Issue #430)
Implements GCC-PHAT beamforming for sound source localization via Jabra mic.
- GCC-PHAT cross-correlation for direction of arrival (DoA) estimation
- Voice activity detection (VAD) using RMS energy + smoothing
- Stereo/quadrophonic channel support (left/right/front/rear estimation)
- ROS2 publishers: /saltybot/audio_direction (Float32 bearing), /saltybot/audio_activity (Bool VAD)
- Configurable parameters: sample_rate, chunk_size, publish_hz, vad_threshold, gcc_phat_max_lag
- Integration-ready for multi-person tracker speaker tracking
Co-Authored-By: Claude Haiku 4.5 <noreply@anthropic.com>
sl-perception
d7b1366d6c