Initial commit of 001code-html Scratch frontend project.

Includes scratch-gui, scratch-vm, scratch-blocks, scratch-render, scratch-l10n, and deployment config.

Co-authored-by: Cursor <cursoragent@cursor.com>

scratch-gui/test/__mocks__/audio-buffer-player.js

@@ -0,0 +1,15 @@
+export default class MockAudioBufferPlayer {
+    constructor (samples, sampleRate) {
+        this.samples = samples;
+        this.sampleRate = sampleRate;
+        this.buffer = {
+            getChannelData: jest.fn(() => samples),
+            sampleRate: sampleRate
+        };
+        this.play = jest.fn((trimStart, trimEnd, onUpdate) => {
+            this.onUpdate = onUpdate;
+        });
+        this.stop = jest.fn();
+        MockAudioBufferPlayer.instance = this;
+    }
+}