update the way environment variables are checked

no longer checking for .env file, just the variables

README.md

@@ -77,7 +77,7 @@ It's also possible to host cobalt via a Docker image, but in that case you'd nee
 That includes:
 | Variable     | Example                          | 
 | --------     | :---                             |
-| `selfUrl`    | `https://co.wukko.me/`           |
+| `selfURL`    | `https://co.wukko.me/`           |
 | `port`       | `9000`                           |
 | `streamSalt` | `randomly generated sha512 hash` |
 | `cors`       | `0`                              |

package.json

@@ -6,7 +6,7 @@
     "exports": "./src/cobalt.js",
     "type": "module",
     "engines": {
-        "node": ">=17.5"
+        "node": ">=18"
     },
     "scripts": {
         "start": "node src/cobalt",

src/cobalt.js

@@ -2,7 +2,6 @@ import "dotenv/config";
 
 import express from "express";
 import cors from "cors";
-import * as fs from "fs";
 import rateLimit from "express-rate-limit";
 
 import path from 'path';
@@ -30,7 +29,7 @@ const corsConfig = process.env.cors === '0' ? { origin: process.env.selfURL, opt
 
 app.disable('x-powered-by');
 
-if (fs.existsSync('./.env') && process.env.selfURL && process.env.streamSalt && process.env.port) {
+if (process.env.selfURL && process.env.streamSalt && process.env.port) {
     const apiLimiter = rateLimit({
         windowMs: 60000,
         max: 25,