Adapt upstream MeshCore #3579 at 7457cff43c22697119e06ad7d192a37de0990403:
retain GC1109 LF standby bias, with checked cold controls before band supply
changes and shutdown. Preserve exclusive LF/HF rails and TX error cleanup.
Reset before boot rail changes and before SPI-dependent hard recovery.
Retain our stronger implementation of #3512 at
d208bfef94ab83280de30ba4a0675ff73b3ecef3. Add regressions for suspect FIFO
contents, failed RX_DONE acknowledgement, and fresh preamble timing.
W12 TX power defaults from #3319 were already included via 65aa1138a.
Validation: 79 targeted native tests; canonical W12 Full repeater and Full
Companion builds, capability checks, app-size and RAM checks passed.
Physical W12 RF envelope, current and LoRa management confirmation remain.
Upstream PRs:
https://github.com/meshcore-dev/MeshCore/pull/3579https://github.com/meshcore-dev/MeshCore/pull/3512https://github.com/meshcore-dev/MeshCore/pull/3319
Adapt the optional onboard-radio probe for RAK3401 and RAK4631 cores using the external RAK13302 image. Preserve SPI1 radio ownership, external FEM startup, and ordinary RAK4631 primary-radio operation.
Probe before boot voltage protection, bound missing-chip waits, release temporary pads, and confirm cold sleep without waking the chip. Add sanitizer-backed host regression tests and CI coverage.
mikecarper