[PCcoding666]

Summary

Fixes a false "not authorized" for system audio introduced with the Core Audio tap (#16).

Root cause (found while testing P2 on a real Mac): a Core Audio process tap only calls back while a tapped process is actually playing. With the Mac silent, an authorized tap delivers no callbacks either. The #16 watchdog treated "no callback within 3 s (twice)" as a denial, so:

• starting capture on a quiet Mac stopped the system-audio lane after ~6 s with "LCT isn't allowed to record system audio";
• the onboarding Allow probe reported "Denied" whenever nothing else was playing.

Fix

• CoreAudioOutputActivity: is any output device running in another process (kAudioDevicePropertyDeviceIsRunningSomewhere and not …IsRunning, so LCT's own microphone engine never counts; LCT's private tap aggregates skipped).
• Capture watchdog counts only audible time: silence waits indefinitely; output running for 3 s with no callbacks → rebuild the tap once → then report not authorized.
• Probe taps LCT's own process (SystemAudioTap(target: .ownProcessOnly)) while LCT plays a short digital silence (SilencePlayer), so audio flows exactly when recording is allowed, independent of other apps.

Test results

• ./Scripts/run_tests.sh: 447 tests, 0 failures, no new warnings; CLT build clean. New tests: nothing playing → never denied; playback starting later → only audible time counts; probe plays and stops silence; capture tap is exclusive-of-LCT while the probe tap is LCT-only. Fakes only — no real tap or audio output in tests.
• Real Mac (macOS 27): capture started with nothing playing → no notice after 15 s; playback started → "authorized" within 1 s. Onboarding Allow with nothing playing → granted, row ✓ (previously "Denied").

🤖 Generated with Claude Code

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