feat: no-de-no-de, now with extra buns (#9683)

BREAKING CHANGE: The REST and RequestManager classes now extend AsyncEventEmitter
from `@vladfrangu/async_event_emitter`, which aids in cross-compatibility
between Node, Deno, Bun, CF Workers, Vercel Functions, etc.

BREAKING CHANGE: DefaultUserAgentAppendix has been adapted to support multiple
different platforms (previously mentioned Deno, Bun, CF Workers, etc)

BREAKING CHANGE: the entry point for `@discordjs/rest` will now differ
in non-node-like environments (CF Workers, etc.)

Co-authored-by: Suneet Tipirneni <77477100+suneettipirneni@users.noreply.github.com>
Co-authored-by: Jiralite <33201955+Jiralite@users.noreply.github.com>
Co-authored-by: suneettipirneni <suneettipirneni@icloud.com>

packages/rest/vitest.config.ts

@@ -0,0 +1,11 @@
+import { defineProject, mergeConfig } from 'vitest/config';
+import configShared from '../../vitest.config.js';
+
+export default mergeConfig(
+	configShared,
+	defineProject({
+		test: {
+			setupFiles: ['./__tests__/setup.ts'],
+		},
+	}),
+);