loraRegionPresetMapFlow
Flow of the firmware's region→modem-preset compatibility map (LoRaRegionPresetMap), populated from org.meshtastic.proto.FromRadio.region_presets during the config handshake (sent after metadata, before channels). Null when the connected firmware predates this message (< 2.8) or after clearLoraRegionPresetMap. The local LoRa config UI uses it to constrain the preset picker to the presets legal in the selected region.