Everywhere: Hoist the Libraries folder to the top-level

Author: https://github.com/trflynn89
Commit: https://github.com/LadybirdBrowser/ladybird/commit/93712b24bf2
Pull-request: https://github.com/LadybirdBrowser/ladybird/pull/2256
Reviewed-by: https://github.com/sideshowbarker

Libraries/LibJS/Tests/builtins/JSON/JSON.stringify-proxy.js

@@ -0,0 +1,11 @@
+test("basic functionality", () => {
+    let p = new Proxy([], {
+        get(_, key) {
+            if (key === "length") return 3;
+            return Number(key);
+        },
+    });
+
+    expect(JSON.stringify(p)).toBe("[0,1,2]");
+    expect(JSON.stringify([[new Proxy(p, {})]])).toBe("[[[0,1,2]]]");
+});