Close the FX reclaimer's undo span at the state-load hook, and expose the drain's direction

A Ctrl-Z mid-span used to close the pre-undo block over post-undo state; it now
terminates at BeginLoadProjectState and stops the drain where it stands.
fxReclaimActivity reports Online/Offline/Idle; fxReclaimPending is unchanged.

src/app/main.cpp

@@ -247,7 +247,15 @@ static void OnTimer()
 static void OnBeginLoadProjectState(bool isUndo, project_config_extension_t* /*reg*/)
 {
     if (isUndo)
+    {
+        // BEFORE the reload request, and the whole reason this is a hook rather than
+        // something the reload's own reapply does on arrival: the reclaimer's undo block
+        // is open for at least kParkHoldMs after every real mode switch, and a switch is
+        // exactly what this undo is rolling back. Closing it here is the last moment it
+        // still closes over the state it was opened on.
+        reasampler::fxReclaimAbandonForStateLoad();
         g_session.requestReload();
+    }
 }
 
 // Intentional no-op: ReaSampler stores state via project EXT STATE, not this