refactored nginx configs

- handle CORS within nginx
- remove allow-headers from CORS
- add custom dynamic error pages
- remove unused fastcgi
- removed OPTIONS backend
- remove previous custom errorDirective
- moved proxy directives to appropiate file

src/middleware/cors.ts

@@ -2,7 +2,6 @@ import { NextFunction, Request, Response } from "express";
 
 export function corsMiddleware(req: Request, res: Response, next: NextFunction): void {
     res.header("Access-Control-Allow-Origin", "*");
-    res.header("Access-Control-Allow-Headers", "X-Requested-With, Content-Type, Accept");
     res.header("Access-Control-Allow-Methods", "GET, POST, OPTIONS, DELETE");
     next();
 }