faster startup and fix asan error

internal/os.c

@@ -34,14 +34,10 @@
 static JSClassID js_dylib_class_id;
 
 static void js_dylib_finalizer(JSRuntime *rt, JSValue val) {
-  void *handle = JS_GetOpaque(val, js_dylib_class_id);
-  if (handle) {
-#ifdef _WIN32
-    FreeLibrary((HMODULE)handle);
-#else
-    dlclose(handle);
-#endif
-  }
+  /* Do NOT dlclose here. Loaded dylibs contain finalizer functions for other
+     JS objects; if the dylib is freed before those objects during
+     JS_FreeContext teardown, calling their finalizers would SEGV.
+     The OS reclaims all loaded libraries on process exit. */
 }
 
 static JSClassDef js_dylib_class = {