Add Proxy Support

[kamuridesu]

Hello! Please, add proxy support. I think is not currently supported by native fetch, so I'm using it with axios, like:

import {NekosAPI} from "nekosapi/v3/index.js";
import { SocksProxyAgent } from "socks-proxy-agent";
import axios, { AxiosResponse } from "axios";

type ProxyAuth = {
    username: string;
    password: string;
}

type CustomProxy = {
    protocol: string;
    host: string;
    port: number;
    auth: ProxyAuth;
}

export const Socks5Proxy: CustomProxy = {
    protocol: 'socks5',
    host: process.env.PROXY_HOST!,
    port: parseFloat(process.env.PROXY_PORT!),
    auth: {
      username: process.env.PROXY_USER != undefined ? process.env.PROXY_USER : "",
      password: process.env.PROXY_PASS != undefined ? process.env.PROXY_PASS : ""
    }
}

function checkResponseCode(response: AxiosResponse<any, any>) {
    if ((response.status > 200 && response.status <= 300)) {
        throw new Error(`An error occurred while fetching data from the server. ${response.statusText}. Status: ${response.status}. ${response.request?.url}`)
    }
}

async function fetchResponse<T>(url: URL): Promise<T> {
    const proxy = process.env.PROXY_HOST != undefined ? Socks5Proxy : false;
    let agent;
    if (proxy) {
        const proxyURL = `${proxy.protocol}://${proxy.auth.username}:${proxy.auth.password}@${proxy.host}:${proxy.port}`;
        agent = new SocksProxyAgent(proxyURL);
    }
    const response = await axios.get(
        url.toString(),
        {
            httpsAgent: agent,
            responseType: "json"
        }
    )
    checkResponseCode(response);
    return <T> await response.data;
}

export class NekosAPIAxiosProxy extends NekosAPI {
    constructor() {
        super();
        (this as any).checkResponseCode = checkResponseCode;
        (this as any).fetchResponse = fetchResponse;
    }
}

[cataclym]

Hi! Thanks for creating this issue
This is certainly something I would not mind implementing, however as you say, native fetch does not support proxies.
I am thinking of using undici or axios, and currently axios seems like the fastest option.

[cataclym]

In 073a7d8 I added (untested) preliminary support.
I am not sure how to test the proxy setup, so if you have the time to test it, I would appreciate that :) npm i https://github.com/cataclym/nekosapi.git

It's setup to read the environment variables same as yours.

[cataclym]

@kamuridesu :)

[kamuridesu]

Thank you, sorry for the late response, I'm traveling right now. I'll test it as soon as possible!

[kamuridesu]

All working! Sorry for taking so long to validate, it's all working fine now, thank you.