Cap Berry GC threshold growth on PSRAM to avoid multi-second stalls (#25044)

Without this, threshold = usage * 2 (default steprate) lets PSRAM
heaps grow unbounded until a GC sweeps tens of thousands of objects
out of a nearly-full pool in one go, costing multiple seconds
(observed: 4.4s freeing 25k objects from a 2.6MB heap). Cap growth to
fixed increments instead, same as the non-PSRAM case, just scaled up
for the bigger heap.

Co-authored-by: Claude Sonnet 5 <noreply@anthropic.com>

tasmota/tasmota_xdrv_driver/xdrv_52_9_berry.ino

@@ -320,7 +320,11 @@ void BerryObservability(bvm *vm, int event, ...) {
         );
 #endif
         // make new threshold tighter when we reach high memory usage
-        if (!UsePSRAM() && vm->gc.threshold > 20*1024) {
+        if (UsePSRAM()) {
+          if (vm->gc.threshold > 200*1024) {
+            vm->gc.threshold = vm->gc.usage + 100*1024;    // increase by 100 KB
+          }
+        } else if (vm->gc.threshold > 20*1024) {
           vm->gc.threshold = vm->gc.usage + 10*1024;    // increase by only 10 KB
         }
       }