gfa-2.17.7-40-g0d67062

Gqrx for AntennaHead

Unofficial interim build of Gqrx — official upstream source plus five
open remote-control commands that haven't landed upstream yet:

• #1463 — l/L FILTER_SHAPE (soft/normal/sharp filter shape)
• #1464 — bookmark download & recall over remote control
• #1446 — input/output device selection over remote control
• dsward2/gqrx#2 — U/u UDP — toggle Gqrx's own UDP audio-streaming button over remote control
• dsward2/gqrx#1 — l/L FILTER_OFFSET — read/write the channel offset within the current passband, without a hardware retune

Built to let AntennaHead's
"Listen to Gqrx" page drive these before they're in an official release.
See AntennaHead/Docs/GQRX_FOR_ANTENNAHEAD_BUILD.md for the build recipe
and LISTEN_TO_GQRX_REMOTE_CONTROL_FEASIBILITY.md for the full feature
design.

This build:

• Developer ID signed, hardened runtime, notarized, stapled — no
  Gatekeeper warning on install
• Two DMGs: Apple Silicon (arm64) and Intel (x86_64)
• Not sandboxed (needs raw USB for RTL-SDR access — see the build doc
  for why)
• Bundle id com.dsward.gqrx-for-antennahead, so it won't collide with
  an official Gqrx install

Not affiliated with or endorsed by the Gqrx project. If these PRs
merge upstream, this build becomes unnecessary — use official Gqrx
instead.