audiohook.c: Improve frame pairing logic to avoid MixMonitor breakage with mixed...

audiohook.c: Improve frame pairing logic to avoid MixMonitor breakage with mixed codecs

This patch adjusts the read/write synchronization logic in audiohook_read_frame_both()
to better handle calls where participants use different codecs or sample sizes
(e.g., alaw vs G.722). The previous hard threshold of 2 * samples caused MixMonitor
recordings to break or stutter when frames were not aligned between both directions.

The new logic uses a more tolerant limit (1.5 * samples), which prevents audio tearing
without causing excessive buffer overruns. This fix specifically addresses issues
with MixMonitor when recording directly on a channel in a bridge using mixed codecs.

Reported-by: Michal Hajek <michal.hajek@daktela.com>
Resolves: #1276
Resolves: #1279