ludic.ui, runtime: the last per-frame allocations in the interface - the top popover found without a list, the popover draw list and the clip stack kept, a select's options in a list the node keeps (and matched to its value without writing the index), a number's text kept on its Value until it changes (value_num_set / Value.num_text), a key's label kept per key code until the layout changes it

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

packages/ludic.ui/backend.ludic

@@ -149,6 +149,7 @@ export state UiState {
   pe_key: string = ""         # the element the pointer is captured by
   pe_btn: int = 0
   pop_list: []UiNode = new []UiNode
+  pop_spare: []UiNode = new []UiNode
   pp_bx: float = 0.0
   pp_by: float = 0.0
   pp_bw: float = 0.0