- Migrate QSettings → AppSettings for connection panel collapsed state
- Add ConnectionPanel::isCollapsed() public getter
- Remove deprecated band memory restore (issue #9)
- All settings now use AppSettings XML format

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

- Migrate QSettings → AppSettings for connection panel collapsed state
- Add ConnectionPanel::isCollapsed() public getter
- Remove deprecated band memory restore (issue #9)
- All settings now use AppSettings XML format

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

* Fix stuck TX by immediately gating MOX on unkey

When turning off MOX, immediately set m_transmitting=false and emit
moxChanged(false) before sending "xmit 0" to the radio. This prevents
TX audio from continuing to stream during the 7-15 second interlock
state transition (UNKEY_REQUESTED → READY) on fw v1.4.0.0.

Also gate TX in RadioModel::setTransmit() for the same reason.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

* Add Hamlib rigctld-compatible CAT control (TCP + PTY)

Implement a rigctld protocol emulator that allows WSJT-X, fldigi, and
other Hamlib-compatible software to control the radio. Includes:

- RigctlProtocol: pure protocol parser/responder (no I/O), supports
  get/set freq, mode, VFO, PTT, split, dump_state, batch commands
- RigctlServer: QTcpServer wrapper, multi-client, per-client state
- RigctlPty: openpty() virtual serial port with /tmp/AetherSDR-CAT symlink

Mode mapping verified against FLEX-8600 fw v1.4.0.0. Thread-safe writes
via QMetaObject::invokeMethod with Qt::QueuedConnection.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

* Add CatApplet GUI, persistent settings, and MainWindow wiring

- CatApplet: settings panel for rigctld TCP, virtual serial port, and
  DAX audio enable/disable with port configuration
- AppletPanel: persistent applet toggle states via QSettings, add CAT
  button; refactor addApplet() to restore saved visibility on startup
- MainWindow: wire up RigctlServer, RigctlPty, DaxStreamManager,
  VirtualAudioBridge; auto-start CAT/DAX based on saved settings;
  save/restore frequency, mode, connection panel collapsed state
- RadioModel: restore last frequency/mode from QSettings on reconnect
- CMakeLists.txt: add all new source files and HAL plugin subdirectory

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

* Fixup: resolve rebase conflicts for PR #11

- Migrate QSettings → AppSettings for connection panel collapsed state
- Add ConnectionPanel::isCollapsed() public getter
- Remove deprecated band memory restore (issue #9)
- All settings now use AppSettings XML format

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

* Style fixes for CatApplet: title bars and toggle buttons

- Replace sectionHeader() with appletTitleBar() for gradient title bars
- Replace QCheckBox enables with QPushButton toggles (green active style)
- Matches STYLEGUIDE.md conventions

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

* Remove DAX shared memory implementation, keep rigctld and TX fix

DAX virtual audio needs PipeWire virtual devices to work with existing
ham radio software (WSJT-X, fldigi, FreeDV). The shared memory IPC
approach has no compatibility with standard audio apps.

Removed:
- DaxStreamManager, VirtualAudioBridge (shared memory IPC)
- macOS HAL plugin (hal-plugin/)
- DAX gain/TX gain sliders and enable button from CatApplet
- All DAX wiring from MainWindow

Kept:
- Hamlib rigctld TCP server (port 4532) + PTY virtual serial port
- CatApplet GUI with rigctld/PTY controls
- TX stuck fix (MOX gating in TransmitModel)
- DAX title bar with "coming soon" placeholder

DAX tracked in issue #15.

Co-Authored-By: pepeforg1234 <pty.11111@gmail.com>
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

* Guard SpectrumWidget::paintEvent against zero-size painting

SEGV occurred in QPainter::drawLine during paintEvent when rigctld
was stopped while WSJT-X was actively polling. The crash was in
operator new (allocation failure), likely triggered by painting with
invalid geometry during a state transition.

Added early return guard when width/height are too small to render.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

* Autostart CAT: rename menu items, save state, start on connect

- Renamed "Autostart CAT/DAX with SmartSDR" to "with AetherSDR"
- Menu items are now checkable toggles, persisted via AppSettings
- When AutoStartCAT is enabled and radio connects, rigctld TCP server
  and PTY virtual serial port start automatically
- Fixes first-launch WSJT-X connection failure (server wasn't running)

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

* Fix CAT server auto-starting: migrate QSettings to AppSettings

CatApplet was reading cat/tcpEnable and cat/ptyEnable from old QSettings
on construction, causing the toggle buttons to fire and auto-start the
server even when Autostart CAT wasn't enabled.

- Removed per-button state persistence (tcpEnable/ptyEnable) — CAT
  auto-start is now solely controlled by the "Autostart CAT with
  AetherSDR" menu item
- Migrated port setting from QSettings cat/tcpPort to AppSettings CatTcpPort
- Removed all QSettings usage from CatApplet

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

* Fix CAT autostart and remove false "not implemented" message

- Exclude wired actions (network, memory, spots, autostart CAT/DAX)
  from the catch-all "not implemented" handler
- Add debug logging to AutoStartCAT to verify it fires on connect
- Use saved CatTcpPort for autostart server port

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

* Split CAT autostart into rigctld and PTY, sync applet buttons

- New "Autostart rigctld with AetherSDR" menu item (TCP server)
- Existing "Autostart CAT with AetherSDR" now controls PTY only
- Both persist independently in AppSettings
- On radio connect, auto-started services sync their CatApplet
  Enable buttons to green via setTcpEnabled()/setPtyEnabled()
- Removed stale auto-start logic from CatApplet::setRigctlPty()

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

* Fix rigctld slow response: flush TCP socket after each write

WSJT-X "Test CAT" took 46 seconds because socket->write() buffered
the dump_state response without flushing. WSJT-X waited for data
that was sitting in Qt's write buffer. Added socket->flush() after
each response write.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

* Fix rigctld delayed commands: use TCP_NODELAY instead of flush

socket->flush() may block if the client isn't reading. Replace with
TCP_NODELAY (LowDelayOption) on client accept to disable Nagle's
algorithm. Responses are sent immediately without buffering delays.

This fixes WSJT-X commands (band change, PTT) being queued for 42+
seconds before executing all at once.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

* Add rigctld command-level debug logging

Log every command received and response sent for diagnosing
WSJT-X connection delays. dump_state response format may need
adjustment for faster NET rigctl handshake.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

---------

Co-authored-by: pepeforg1234 <pty.11111@gmail.com>
Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>

- Rule #11: Use AppSettings, NEVER QSettings (prevents future regressions)
- AI-to-AI Debugging section: describes how contributor AIs can open
  issues for the maintainer's AI to analyze and respond to

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

…/shim

- Delete default constructor (= delete) to prevent null-vector deref (aethersdr#1)
- Remove noexcept from processBlock overrides, buildPrefilter, buildRrcLowpass
  — allocating ops inside noexcept terminate on OOM (aethersdr#2)
- Unconditionally call lane.demod->reset() on gate-close so DPLL/AGC
  are not left stale across silence gaps (aethersdr#3)
- Add lastHdlcFrameStartSampleIndex with 10-sample dedup window to
  prevent 9x inflation of totalHdlcFrameStarts in A+ mode (aethersdr#4)
- Record demod diagnostics from lanes.size()/2 (middle slicer) instead
  of lane 0 (weakest slicer in A+ mode) (aethersdr#6)
- Fix int*int overflow in duplicateWindowSamples: cast first operand
  to quint64 before multiply (aethersdr#8)
- Extract vhfModeLayout() free function; replace two switch copies
  in configure() and ax25DemodLaneCount() (aethersdr#10)
- AfskDemodWrapper<Demod,Result> template replaces two identical structs;
  using aliases preserve LibmodemAfskDemod / DirewolfAfskDemod names (aethersdr#11)
- Delete dead try_demodulate(double, uint8_t&) overload; all callers
  use the demod_result overload (aethersdr#12)
- Add pushLP() helper for LP ring-buffer writes; replaces 4 open-coded
  stores with manual bump in try_demodulate (aethersdr#13)

Not fixed (intentional):
  aethersdr#5 — phaseOffsetSamples=0 on all A+ lanes: DPLL pull-in makes
       phase stagger redundant (kPllSearchingInertia=0.50 locks in 4-5
       symbols from any starting phase, matching Direwolf behaviour)
  aethersdr#7 — Normal polarity hard-coded in setModemProfile: pre-existing in
       main since PR aethersdr#3279; no polarity UI or AppSettings key exists
  aethersdr#9 — DC-sum normalisation in buildRrcLowpass: correct for envelope
       detector on IQ baseband; energy norm only valid for matched filter

Principle VIII.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

…/shim

- Delete default constructor (= delete) to prevent null-vector deref (aethersdr#1)
- Remove noexcept from processBlock overrides, buildPrefilter, buildRrcLowpass
  — allocating ops inside noexcept terminate on OOM (aethersdr#2)
- Unconditionally call lane.demod->reset() on gate-close so DPLL/AGC
  are not left stale across silence gaps (aethersdr#3)
- Add lastHdlcFrameStartSampleIndex with 10-sample dedup window to
  prevent 9x inflation of totalHdlcFrameStarts in A+ mode (aethersdr#4)
- Record demod diagnostics from lanes.size()/2 (middle slicer) instead
  of lane 0 (weakest slicer in A+ mode) (aethersdr#6)
- Fix int*int overflow in duplicateWindowSamples: cast first operand
  to quint64 before multiply (aethersdr#8)
- Extract vhfModeLayout() free function; replace two switch copies
  in configure() and ax25DemodLaneCount() (aethersdr#10)
- AfskDemodWrapper<Demod,Result> template replaces two identical structs;
  using aliases preserve LibmodemAfskDemod / DirewolfAfskDemod names (aethersdr#11)
- Delete dead try_demodulate(double, uint8_t&) overload; all callers
  use the demod_result overload (aethersdr#12)
- Add pushLP() helper for LP ring-buffer writes; replaces 4 open-coded
  stores with manual bump in try_demodulate (aethersdr#13)

Not fixed (intentional):
  aethersdr#5 — phaseOffsetSamples=0 on all A+ lanes: DPLL pull-in makes
       phase stagger redundant (kPllSearchingInertia=0.50 locks in 4-5
       symbols from any starting phase, matching Direwolf behaviour)
  aethersdr#7 — Normal polarity hard-coded in setModemProfile: pre-existing in
       main since PR aethersdr#3279; no polarity UI or AppSettings key exists
  aethersdr#9 — DC-sum normalisation in buildRrcLowpass: correct for envelope
       detector on IQ baseband; energy norm only valid for matched filter

Principle VIII.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

) (#3799)

## Summary
Fixes the weekly **ASan/UBSan** job failure in
`cwx_local_keyer_drift_test` (#3740): a heap-use-after-free at `Fixture`
teardown.

This is a **test-only** lifetime bug — no production code change.

## Root cause
`Fixture` members destruct in reverse declaration order. With `keyer`
declared **before** `states`, `states` is freed **first**:

```cpp
struct Fixture {
    TestKeyer keyer;          // declared first  -> destroyed LAST
    std::vector<int> states;  // declared last   -> destroyed FIRST  (freed)
    Fixture() { keyer.setOnKeyDownChange([this](bool d){ states.push_back(d?1:0); }); }
};
```

When a test leaves the keyer **key-down** at teardown, the keyer's
destructor still fires the callback into the already-freed vector:

`~CwxLocalKeyer()` (`CwxLocalKeyer.cpp:48`) → `keyUpIfDown()` (`:235`) →
`emitKeyDown(false)` (`:229`) → installed callback →
`states.push_back(0)` **into freed memory**.

`emitKeyDown` early-returns when the requested state already matches
`m_lastEmittedKeyDown`, so only a test that ends **key-down** trips it.
`testLateTicksShortenNextWait` starts `"S"`, ticks twice, and never
drains or stops — leaving the key down — which is exactly the case the
ASan trace points at.

## Fix
Reorder the two members so `states` is declared first (destroyed last)
and outlives `keyer`. The destructor callback now writes into a live
vector. Robust against any future test that leaves the keyer keyed-down.

## Why production is unaffected
- `MainWindow` resets the keyer **before** the audio sink it calls into.
- The sidetone callback is null-guarded.

So no runtime UAF is reachable — this only broke the sanitizer job
(`priority: low`).

## Proof — agent automation bridge N/A; this is a sanitizer/unit-test
bug
The automation bridge drives the running app and can't observe a
unit-test teardown UAF, so the proof here is a direct **before → after**
ASan run. The keyer's worker thread makes the live test's
key-up/key-down state at teardown timing-dependent (hence a *weekly*
flake); to make the proof deterministic I replicated the exact
synchronous `TestKeyer(spawnWorker=false)` path and the
`testLateTicksShortenNextWait` sequence (which leaves `states` at
`size=3, cap=4` — matching the CI trace's "12 bytes inside of 16-byte
region"):

**Before (buggy `states`-freed-first order)** — reproduces the CI stack
frame-for-frame:
```
==ERROR: AddressSanitizer: heap-use-after-free ... WRITE of size 4
  #9  AetherSDR::CwxLocalKeyer::emitKeyDown(bool)  CwxLocalKeyer.cpp:229
  #10 AetherSDR::CwxLocalKeyer::keyUpIfDown()      CwxLocalKeyer.cpp:235
  #11 AetherSDR::CwxLocalKeyer::~CwxLocalKeyer()   CwxLocalKeyer.cpp:48
SUMMARY: AddressSanitizer: heap-use-after-free in std::vector<int>::emplace_back
exit=134
```

**After (fixed `states`-outlives-`keyer` order)** — clean:
```
states=3 key DOWN; teardown fires keyUpIfDown into LIVE states
OK: clean teardown
exit=0
```

**Real test, fixed, built with `-fsanitize=address`:** `54 OK, 0 FAIL`,
no ASan report, `All tests passed.`

## Related
- #3740 (this issue) — `good first issue`, `sanitizer`, `asan-ubsan`,
`CW`.

Fixes #3740

💻 Generated with Claude Code (Opus 4.8) with architecture by @jensenpat

Co-authored-by: Claude Opus 4.8 <noreply@anthropic.com>