feat(Client): Support Proxy

- https://github.com/discordjs/discord.js/issues/3039#issuecomment-1033955220
- #283
(not tested yet)

Co-Authored-By: Nguyễn Hồng Đức <hongducyb123@gmail.com>

package.json

@@ -66,6 +66,7 @@
     "form-data": "^4.0.0",
     "json-bigint": "^1.0.0",
     "node-fetch": "^2.6.1",
+    "proxy-agent": "^5.0.0",
     "safe-base64": "^2.0.1-0",
     "string_decoder": "^1.3.0",
     "ws": "^8.8.1"