fix(processor): close S-VIEW-4 previewVelocity persistence loop

Add previewVelocity_ member to ReaSamplerProcessor; populate it in
getState and restore it in setState so the field round-trips in the
plugin, not just in the pure unit test. Clamp 1..127 at the
deserialize read boundary in sample_map.cpp.

src/vst/reasampler_processor.cpp

@@ -197,6 +197,9 @@ tresult PLUGIN_API ReaSamplerProcessor::setState(IBStream* state) {
         channelMode_ = cs.channelMode;
     }
     applyOutputArrangement(cs.channelMode);
+    // S-VIEW-4: restore the per-instance preview velocity. No mutex — setState is a load-time
+    // call serialized by the host; there is no concurrent writer before Wave 2.
+    previewVelocity_ = cs.previewVelocity;
     // Rebuild from the restored state (off-thread — setState is a load-time call).
     reloadFromBank();
     return kResultOk;
@@ -217,6 +220,7 @@ tresult PLUGIN_API ReaSamplerProcessor::getState(IBStream* state) {
         std::lock_guard<std::mutex> lock(assignMarkerMutex_);
         state_out.lastConsumedAssignGeneration = lastConsumedAssignGeneration_;  // S8 reader marker
     }
+    state_out.previewVelocity = previewVelocity_;  // S-VIEW-4: persist the preview strike velocity
     const std::vector<std::uint8_t> bytes = serializeComponentState(state_out);
     if (!bytes.empty()) {
         const tresult wr = state->write(const_cast<std::uint8_t*>(bytes.data()),

src/vst/reasampler_processor.h

@@ -250,6 +250,12 @@ private:
     // NOT read on the audio thread.
     std::int64_t lastSeenBankGeneration_ = -1;
 
+    // S-VIEW-4 preview-trigger velocity (MIDI 1..127). Persisted in component state (v6) so the
+    // user's chosen strike velocity survives a project save/reload. No concurrent writer before
+    // Wave 2 (no editor knob yet) — setState and getState are the sole accessors, both on the
+    // load/save thread (host-serialized). Default kPreviewVelocityDefault (64).
+    std::uint8_t previewVelocity_ = kPreviewVelocityDefault;
+
     // Latched from setupProcessing so setActive/reload can size against it. Read
     // off-thread only. 0.0 is explicitly invalid — setupProcessing sets the real host rate
     // before any audio, and reloadFromBank guards on it before use.

src/vst/sample_map.cpp

@@ -628,7 +628,11 @@ ComponentState deserializeComponentState(const std::vector<std::uint8_t>& bytes,
     if (!r.ok) return out;  // truncated before/inside the marker -> empty (marker 0 holds)
     const std::uint8_t previewVel = r.u8();
     if (!r.ok) return out;  // truncated before the velocity byte -> empty (mid default holds)
-    out.previewVelocity = previewVel;
+    // Clamp to the documented MIDI 1..127 range: a 0 byte (or any out-of-spec value from a
+    // corrupt blob) falls back to the mid default rather than silencing the preview trigger.
+    out.previewVelocity = (previewVel >= 1 && previewVel <= 127)
+                              ? previewVel
+                              : kPreviewVelocityDefault;
     const std::uint32_t idLen = r.u32();
     out.selectionId = r.str(idLen);
     if (!r.ok) { out.selectionId.clear(); return out; }  // truncated id -> empty