Note confirmed ring duration and silent sound 0

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

CLAUDE.md

@@ -62,7 +62,8 @@ From Tuya's definition for a sibling product (tuya-local issue #3821). See the R
 - Byte 8 isn't per alarm. Every DP127 write sets all 4 to the current radio station, so there's no per-alarm station control.
 - Byte 10 is forced to 0 without the light bit, and writing 0 clears the light bit.
 - Byte 11: above 1 becomes 1.
-- What byte 4 actually does to ring length isn't confirmed. A test ring wasn't observed stopping.
+- Byte 4 is the ring length in minutes: set to 10, a ring ran from 18:16 to 18:26 and the owner saw it stop.
+- Sound 0 is silent. In Sound + Light mode, the light still came on and no sound played.
 - Radio Volume and station writes are ignored with the radio off. With it on, both work, and the station stays selected after turning it off.
 - Keep `default_transition_length` at 0. A transition sends about 50 MCU writes a second.
 - LibreTiny before v1.14.0 can hang after a software restart or OTA until powered off for about 30 seconds (LibreTiny issue #396). The config pins v1.14.0. Drop the pin once ESPHome defaults to it or newer.