Close derived-bake-window review findings: NaN-guard remaining wire doubles, pin Trigger-span agreement, retire dead quantizer

Guards params_payload.cpp's filter-tail seconds and both keyTrack sites against NaN; pins Voice::start's Trigger-span formula against trigger_seam; retires unused shortestDivisionAtLeast.

tests/test_sampler_core.cpp

@@ -1380,6 +1380,34 @@ static void testTriggerEdgeCases() {
     }
 }
 
+// --- Trigger out-of-domain lengthFraction: Voice::start's inline copy of trigger_seam's
+// formula (map/trigger_seam.h) must clamp the same way the shared formula does — a
+// frac > 1.0 never plays past the post-start span, and a NaN frees immediately rather than
+// reaching the round()/static_cast<int64_t> undefined on a non-finite value. Pins the second
+// implementation directly; test_trigger_seam.cpp pins the first.
+static void testTriggerFracAboveOneClampsToSpan() {
+    // 150% length on a 200-frame sample -> clamped to the full 200-frame post-start span,
+    // not 300 frames (which would read off the end of the PCM).
+    SampleData km = (triggerSample(200, 1.5, 0, 0));
+    VoiceEngine eng(1, km);
+    eng.noteOn(60, 127);
+    std::vector<AudioSample> out;
+    eng.render(out, 220);
+    for (std::size_t i = 0; i < 200; ++i) CHECK(out[i] > 0.5f);
+    for (std::size_t i = 200; i < 220; ++i) CHECK(approx(out[i], 0.0, 1e-6));
+    CHECK(eng.activeVoiceCount() == 0);  // frees exactly at frameCount
+}
+
+static void testTriggerFracNaNFreesImmediately() {
+    SampleData km = (triggerSample(200, std::nan(""), 5, 5));
+    VoiceEngine eng(1, km);
+    eng.noteOn(60, 127);
+    std::vector<AudioSample> out;
+    eng.render(out, 50);
+    for (float v : out) CHECK(approx(v, 0.0, 1e-6));
+    CHECK(eng.activeVoiceCount() == 0);  // playLen 0 -> frees at start, no sound
+}
+
 // --- Trigger ignores note-off (S15): the one-shot plays through regardless. ---
 static void testTriggerIgnoresNoteOff() {
     SampleData km = (triggerSample(200, 0.5, 0, 0));
@@ -2908,6 +2936,8 @@ int main() {
     testTriggerLengthWithStart();
     testTriggerAhdFadeShape();
     testTriggerEdgeCases();
+    testTriggerFracAboveOneClampsToSpan();
+    testTriggerFracNaNFreesImmediately();
     testTriggerIgnoresNoteOff();
 
     // S16 — pitch engine + pitch envelope.