docs: add video upload example

examples/upload/index.ts

@@ -0,0 +1,35 @@
+import { readFileSync, writeFileSync, existsSync } from 'fs';
+import { Innertube, UniversalCache } from 'youtubei.js';
+
+const creds_path = './my_yt_creds.json';
+const creds = existsSync(creds_path) ? JSON.parse(readFileSync(creds_path).toString()) : undefined;
+
+(async () => {
+  const yt = await Innertube.create({ cache: new UniversalCache() });
+  
+  yt.session.on('auth-pending', (data: any) => {
+    console.info(`Hello!\nOn your phone or computer, go to ${data.verification_url} and enter the code ${data.user_code}`);
+  });
+
+  yt.session.on('auth', (data: any) => {
+    writeFileSync(creds_path, JSON.stringify(data.credentials));
+    console.info('Successfully signed in!');
+  });
+
+  yt.session.on('update-credentials', (data: any) => {
+    writeFileSync(creds_path, JSON.stringify(data.credentials));
+    console.info('Credentials updated!', data);
+  });
+
+  await yt.session.signIn(creds);
+  
+  const file = readFileSync('./my_awesome_video.mp4');
+  
+  const upload = await yt.studio.upload(file.buffer, {
+    title: 'Wow!',
+    description: new Date().toString(),
+    privacy: 'UNLISTED'
+  });
+
+  console.info('Done!');
+})();