Summary

Cherry-picks @jensenpat's CW keyboard + MIDI controls work from PR #2361 onto a clean base, plus three follow-up fixes that came out of testing the cherry-pick locally.

Commits squashed in

• Add CW keyboard and MIDI controls (Add CW keyboard USB HID and MIDI keying controls #2361) — cherry-pick of jensenpat's third commit only; the netCW timing/trace work from his first two commits is already on main via Fix and trace netCW keying for straight key and iambic CW #2336. The 3-way merge cleanly resolved the m_lastCwPaddle*/m_lastCwMidi* atomic naming overlap by adopting the more descriptive _Paddle* names everywhere — option 2 from the original review.
• KeyboardMapWidget: fix J tile mapping to Qt::Key_I — pre-existing one-character typo in the on-screen keyboard widget; the J tile was bound to Qt::Key_I, so binding a shortcut to J in the editor selected I instead.
• MainWindow: don't block CW/Space PTT shortcuts during slider lease — clicking the CW delay slider triggered s_sliderShortcutLeaseActive which blocked the momentary CW key handler and Space PTT for 2+ seconds. Splits the helper: textInputCaptured() for actual text widgets only, shortcutInputCaptured() keeps the slider-lease check for the QShortcut dispatch path.
• Honor cw break_in setting for keyboard CW keying — RadioModel::sendCwKey and the iambic keyer's onPaddleEvent both wrapped each key in a cw ptt 1...cw ptt 0 envelope. That made break-in OFF a no-op (auto-PTT forced TX anyway) and killed the QSK hang time with break-in ON. Strips the auto-PTT in both paths so the radio's break-in setting decides TX behavior, matching SmartSDR.

Verification

• Build clean on Linux (RelWithDebInfo).
• shortcut_manager_test, midi_settings_test, radio_status_ownership_test all pass.
• Hardware tested by @ten9876 against FLEX-8600 fw 4.1.5: keyboard straight key, MIDI straight key, paddle keys, break-in OFF blocks auto-PTT, break-in ON honors break_in_delay, slider drag no longer freezes CW shortcuts.

Closes #2361.

Co-authored-by: jensenpat [email protected]
Co-authored-by: Codex [email protected]
Co-Authored-By: Claude Opus 4.7 (1M context) [email protected]