Bake window derives itself: %-knob fold, declick pad, Gate held to exhaustion, preview velocity; Hold is the one knob a loop needs

src/core/instrument/map/sample_map.h

@@ -15,6 +15,7 @@
 #include "core/model/bank_book.h"       // BankBook::deserialize (shared bank JSON parse)
 #include "core/instrument/engine/play_params.h"  // SampleData, SampleLoop, PlayParams
 #include "core/instrument/map/play_seconds.h"    // PlaySeconds (the stored seconds value layer)
+#include "core/instrument/note/musical_division.h"  // Division (the bake hold's value domain)
 #include "core/capture/wav_codec.h"        // parseWavLayout, extractFloatFrames (shared WAV parse)
 
 namespace reasampler::instrument::map {
@@ -188,6 +189,12 @@ struct InstrumentParams {
     // tier-0 AHDSR seconds (0.003 attack / 0.060 release), hold 0, no fades, Preserve pitch
     // engine, pitch env off. An older blob lacking this tail lifts to exactly these.
     PlaySeconds play;
+
+    // How long the resample bake holds the gate. Read ONLY when the bake window cannot be
+    // derived — a Gate voice over an active sustain loop, which sounds indefinitely
+    // (bake_plan.h's bakeWindowNeedsHold is the predicate). Default one bar; a blob predating
+    // the field lifts to it, and no other bake changes.
+    note::Division bakeHold = note::makeDivision(2, note::DivisionModifier::Straight);
 };
 
 // The loaded capture resolved for decode + build: project-relative WAV path (file seam)