fix to make it build on all platforms

lynglib/src/wasmJsMain/kotlin/net/sergeych/lyng/PerfDefaults.wasmJs.kt

@@ -16,4 +16,6 @@ actual object PerfDefaults {
     actual val PRIMITIVE_FASTOPS: Boolean = true
     // Conservative default for non-JVM until validated
     actual val RVAL_FASTPATH: Boolean = false
+    // Regex caching: disabled by default on WasmJS until validated
+    actual val REGEX_CACHE: Boolean = false
 }