ludic.ui: string matching compares in place - at_alias, lk_in, colours and every s[a..b] == p made a string per position tried, per rule, per element, per frame (a benchmark page: ~3 MB -> 256 KB a frame)

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

packages/ludic.ui/env.ludic

@@ -84,7 +84,7 @@ export function ui_err(ui_st: mut UiState, msg0: string) -> void {
 function ui_has(s: string, part: string) -> bool {
   let n = len(part)
   for i in 0 .. len(s) - n + 1 {
-    if s[i..i + n] == part { return true }
+    if sat(s, i, part) { return true }
   }
   return false
 }