Adds AddSend for Param::uaux at CAN ID 0x210, bit 0, length 8, gain=10.
Transmits 12V aux battery voltage in decivolts/0.1V steps (e.g. 125 = 12.5V).
VCU reads byte 0 of 0x210 for 12V battery protection logic per SKUDAK-448.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>