Enable CONFIG_FREERTOS_USE_TRACE_FACILITY and
CONFIG_FREERTOS_GENERATE_RUN_TIME_STATS so PROFILE command reports
per-task CPU usage. Increase cmd_task stack from 4KB to 6KB — was
down to 516 bytes free with current PROFILE reply size.
Dual OTA partition table (ota_0/ota_1, 1920 KB each) on 4MB flash.
Firmware gains OTA command, LED_OTA double-blink, version in STATUS,
and automatic rollback validation. Pi-side esp-ota tool serves firmware
via HTTP and orchestrates the update flow. esp-fleet gains ota subcommand.