Strip FX writes from the Design View mode switch; split view.cpp into park/lanes/reconcile/tracks and add the record-scoped undo repair pass

src/app/main.cpp

@@ -38,7 +38,9 @@
 #include "shell/panel/panel_input.h"             // bankPanelRefresh / bankPanelNotifyProjectLoaded
 #include "shell/panel/panel_window.h"            // panel lifecycle (init/toggle/open-query/shutdown)
 #include "shell/persist/session.h"               // ReaSamplerSession
-#include "shell/view/view.h"                     // reconcileManagedLanes / applyMode
+#include "shell/view/view.h"                     // applyMode
+#include "shell/view/view_lanes.h"               // reconcileManagedLanes
+#include "shell/view/view_reconcile.h"           // reconcileAppliedFlags
 
 namespace capture = reasampler::capture;
 
@@ -205,6 +207,11 @@ static void OnTimer()
         // the cross-session source of truth) BEFORE reapplying visibility. Never
         // re-mints, never mass-tags.
         reasampler::reconcileManagedLanes(g_session.view(), nullptr);
+        // An undo/redo reload also arrives here, and REAPER's undo does not restore
+        // the visibility flags a park drove (UNDO_STATE_TRACKCFG does not carry them).
+        // Repair the tracks the reloaded model no longer records BEFORE the reapply,
+        // which only ever drives tracks the model still records.
+        reasampler::reconcileAppliedFlags(g_session.view(), nullptr);
         reasampler::applyMode(g_session.view(), g_session.view().activeModeId(), nullptr);
     }