fix(14.2): add 30s probe timeout to prevent indefinite silence encoding

The probe phase broadcast indefinitely when measurement never completed
(e.g., solo or peer on older build without instamode fix). After 30s the
Instatalk switches to PTT-driven mode regardless, eliminating CPU spikes.

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

Author: mkschulze

juce/NinjamRunThread.cpp

@@ -380,6 +380,7 @@ void NinjamRunThread::handleStatusChange(NJClient* client, int currentStatus)
                 },
                 &processor);
             lastInstatalkPtt_ = true;  // matches initial broadcasting=true (probe phase)
+            probeDeadlineMs_ = juce::Time::currentTimeMillis() + 30000;  // 30s probe window
 
             // Reset measurement state for new session (allows re-measurement per review concern #5).
             client->resetInstaMeasurement();
@@ -528,7 +529,9 @@ void NinjamRunThread::syncInstatalkBroadcast(NJClient* client)
     // This avoids continuous Vorbis encoding of silence (which caused CPU spikes
     // at every interval boundary) while still allowing automatic probe measurement.
     bool measured = processor.instaMeasurementBroadcast.load(std::memory_order_relaxed);
-    bool want = measured
+    bool probeExpired = probeDeadlineMs_ > 0
+        && juce::Time::currentTimeMillis() > probeDeadlineMs_;
+    bool want = (measured || probeExpired)
         ? processor.pttActive.load(std::memory_order_relaxed)   // PTT-driven
         : true;                                                  // probe: always on
 

juce/NinjamRunThread.h

@@ -53,6 +53,7 @@ class NinjamRunThread : public juce::Thread
 
     // Phase 14.2: track PTT state to toggle Instatalk broadcasting
     bool lastInstatalkPtt_ = false;
+    juce::int64 probeDeadlineMs_ = 0;  // probe phase timeout (0 = not set)
 
     // Prelisten connection metadata (stored from PrelistenCommand for event emission)
     std::string prelistenHost_;