- Add freq_a command: sets VFO A regardless of active VFO; fixes A=B and
SWAP when VFO B is active (prev. sent freq_b which overwrote wrong VFO)
- Add pend("freq") to B=A / A=B / SWAP to guard local display during round-trip
- RX step attenuator: HPSDRNetwork.SetStepAtten → bytes 1442/1443 in HP packet;
WebServer attn command; MainForm FAtten + SyncWebAttn; attSel.onchange in JS
- TUN mode: set_tun WebSocket command wired to ApplyTUN(); toneBtn toggles
with on/off highlight and pending protection; tuning field in state JSON
- FNP button opens semi-transparent filter overlay (10 buttons, 5×2 grid)
with mode-appropriate widths (SSB/CW/AM/FM); active filter highlighted;
cur.filter_bw updated immediately on click so passband redraws within 50ms
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>