Calculate LoRa airtime from the exact LDRO value supplied to SetModulationParams instead of inferring it from symbol time.
Keep transmit_result airtime in microseconds for both LoRa and GFSK, using integer Hz math and 64-bit ceil division to avoid truncation errors.
Reapply modulation parameters during async TX flush so the estimator and the bytes sent to the radio stay in sync, and add a compile-time check for the intended SF7/BW125 implicit 6-byte airtime.
Add CONFIG_LLCC68_MAX_PAYLOAD_LENGTH with a default of 128 bytes and a hardware-bounded range of 1..255.
Wire both the C++ and raw C LLCC68 payload buffer constants to the Kconfig value so application builds can tune radio buffer RAM without editing headers.
Rename the fixed-length 100k preset from GMSK to GFSK and expose rx_bandwidth_hz() next to the GfskRxBandwidth enum so applications can report configured bandwidth without carrying driver-specific lookup tables.
Add a fixed 6-byte 100 kbps GMSK profile matching the health-band telemetry packet, plus FSK packet-status helpers for RSSI and error checks. Expose instantaneous RSSI reads for CCA and image calibration for 430-440 MHz GFSK bring-up.
crosstyan