fix(drop-fx): inject via .vstpreset + TrackFX_SetPreset (vst_chunk is REAPER-framed, raw bytes silently no-op); FX hotspot now prefix tcp.fx*/mcp.fx*/fx_*

src/bank_panel.cpp

@@ -63,7 +63,7 @@
 #include "footer_bar.h"    // pure footer LEFT-group layout: toggle + count + Tail button (L4)
 #include "guid_diff.h"     // GuidBaseline — new-content detection (D2 Wave 2)
 #include "ingest.h"        // ingestDroppedFiles — S8 drop-onto-panel ingest
-#include "instrument_drop.h"      // pure buildInstrumentDropChunk — the vst_chunk blob (S17)
+#include "instrument_drop.h"      // pure buildInstrumentDropPreset — the .vstpreset payload (S17)
 #include "instrument_drop_win.h"  // resolveFxDropTarget / performInstrumentDrop shell (S17)
 #include "item_read.h"     // itemGuid / itemLaneName — shared item-read seam (D2 W3-B)
 #include "lane_keys.h"     // managed/manual lane heuristic (D2 Wave 2)
@@ -3089,8 +3089,8 @@ void onLBtnUp(int x, int y) {
         // gesture never armed for a multi payload), so dragSampleIds.front() is the capture.
         if (g_panel.instrumentDropTrack && g_panel.dragSampleIds.size() == 1) {
             const std::string sampleId = g_panel.dragSampleIds.front();
-            const std::string chunk = buildInstrumentDropChunk(sampleId);
-            performInstrumentDrop(g_panel.instrumentDropTrack, chunk);
+            performInstrumentDrop(g_panel.instrumentDropTrack,
+                                  buildInstrumentDropPreset(sampleId));
             // Read-only over the bank + arrange: the ONLY mutations are the new FX instance +
             // its state (both undoable in performInstrumentDrop). No book change, no ext-state,
             // no dirty-mark here.