view: split the deferred FX-park drain by kind — restores stay forced, parks go one FX per idle tick behind a 1s coalescing delay

A rapid A→B→A flip now costs no plugin work: the restore cancels the still-pending
park outright. A park that has already written one FX carries a `partial` flag and is
superseded by its inverse rather than cancelled, so a half-parked chain is never stranded.

src/app/main.cpp

@@ -196,9 +196,12 @@ static void OnTimer()
     } else {
         // A mode switch applies its visibility/routing writes synchronously and
         // leaves the per-FX offline work here, so the new mode paints before the
-        // plugins unload. Idle cost is one empty test. Skipped on a load tick so
-        // the reapply's own intents defer one tick like any other switch's.
-        reasampler::drainDeferredFxParks();
+        // plugins move. Split by intent kind: restores whole (nothing may persist
+        // over a half-applied one), parks one FX per tick. Idle cost is one empty
+        // test each. Skipped on a load tick so the reapply's own intents defer one
+        // tick like any other switch's.
+        reasampler::drainDeferredFxRestores();
+        reasampler::tickDeferredFxParks();
     }
 
     reasampler::bankPanelRefresh();  // cheap fingerprint compare; no-op when unchanged/closed