getEstAirtimeFor() set LDRO from `sf >= 11`, correct only at BW125. Now
matches the driver's should_enable_ldro() (t_sym > 16.38 ms) so the
estimate's DE tracks hardware DE on every SF/BW. Also drop dead
calcRxDelay() + unused MAX_RX_DELAY_MILLIS.
every LBT-retried flood packet loses its priority (fixed)
witching between LBT and non-LBT mode (or any cad.mode change) could silently skip full reconfiguration and leave the radio in the wrong mode (fixed)
Add .gitattributes rules so .c/.h/.cpp/.hpp are always stored as LF
(prevents EOL drift from editors with autocrlf-true defaults), and
renormalize the 30 source files that had drifted to CRLF in the index.
Pure mechanical change — `git diff --ignore-cr-at-eol` is empty.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>