feat(gacha): add /api/gachabeta toon-shaded wish style

The beta wish renders an 8-second astrology-themed night sky in toon
shading through a perspective action camera: it dollies toward a hero
cloud, a comet lights the cloud's rim from behind and bursts through it,
the camera chases the comet as its flare builds to a starburst, and the
label appears with an S, SS, or SSS rank. It shares the /api/gacha request
contract and render slots.

renderer/scripts/api-smoke.js

@@ -65,6 +65,21 @@ try {
   }
 
   console.log(`api-smoke gacha: ${gacha.rawPayload.byteLength} bytes`);
+
+  const beta = await app.inject({
+    method: 'POST',
+    url: '/api/gachabeta',
+    headers: {
+      authorization: 'Bearer smoke-token',
+    },
+    payload: {label: 'Bún bò', rarity: 5},
+  });
+
+  if (beta.statusCode !== 200 || beta.rawPayload.subarray(4, 8).toString() !== 'ftyp') {
+    throw new Error(`Expected gachabeta MP4, got ${beta.statusCode}: ${beta.body.slice(0, 200)}`);
+  }
+
+  console.log(`api-smoke gachabeta: ${beta.rawPayload.byteLength} bytes`);
 } finally {
   await app.close();
 }

renderer/scripts/render-fixtures.js

@@ -1,6 +1,6 @@
 import {mkdir, writeFile} from 'node:fs/promises';
 import path from 'node:path';
-import {renderGachaVideo} from '../src/render/render-gacha.js';
+import {renderGachaBetaVideo, renderGachaVideo} from '../src/render/render-gacha.js';
 import {renderWheelGif} from '../src/render/render-gif.js';
 
 const smoke = process.argv.includes('--smoke');
@@ -72,3 +72,12 @@ for (const fixture of smoke ? fixtures.slice(0, 1) : fixtures) {
 for (const fixture of smoke ? gachaFixtures.slice(0, 1) : gachaFixtures) {
   await save(`${fixture.name}.mp4`, await renderGachaVideo(fixture.request, {timeoutInMilliseconds: 30000}));
 }
+
+const betaFixture = {
+  label: 'Bún bò',
+  rarity: /** @type {const} */ (5),
+  fps: /** @type {const} */ (24),
+  width: /** @type {const} */ (640),
+  seed: 7,
+};
+await save('gachabeta-5-star.mp4', await renderGachaBetaVideo(betaFixture, {timeoutInMilliseconds: 30000}));