audio: add dynamic playback and capture route selection - #613

The important calculation is: next_offset = offset + 8 + chunk_size + (chunk_size & 1)

where:

• 8 = 4-byte chunk ID + 4-byte size
• chunk_size = payload length
• chunk_size & 1 = 1 when payload length is odd, otherwise 0

One robustness improvement

Because _read_exact() may raise an exception if the file is unexpectedly truncated or changes after file_bytes was obtained, you could defensively handle that case:

try:
chunk_header = _read_exact(handle, 8)
except (EOFError, OSError):
return False, tuple(chunk_names)

Thanks for checking the chunk alignment. Yes, the calculation includes the 8-byte header and the padding byte for an odd-sized payload.

For the truncation case, _read_exact() raises WavValidationError, not EOFError. That exception, along with OSError from reading or seeking, already propagates through parse_wave() to the CLI exception handler, which emits a structured ERROR and returns exit code 2 rather than an unhandled traceback.

I would retain that propagation here. Returning False instead would classify the problem as an unrecognized trailing-chunk layout, which the caller treats as a warning, potentially allowing validation to pass despite an I/O failure. Also, the proposed except (EOFError, OSError) would not catch this helper's short-read exception. No additional catch is needed for the reported CLI failure path.