subpath/baseurl option

[abd3-13]

Firstly thanks for the app, nice and simple one place media app, It would be nice to access it on subpaths/subdirectory like 10.5.2.4:8585/reiverr or media.home.com/reiverr

some feedback":
1 - an option in setting to add base url like '/reiverr/''
2 - or an option to add base url on env variable
3 - or make it reverse proxy on subpath compatible

i have tried to make a location block on my nginx proxy it works on the homepage but breaks on sources,library,settings discover pages

nginx:

location /rei/ {
        proxy_set_header    X-Real-IP  $remote_addr;
        proxy_set_header    X-Forwarded-Proto $scheme;
        proxy_set_header    X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_set_header    Host $http_host;
        proxy_http_version  1.1;
        proxy_set_header    Upgrade $http_upgrade;
        proxy_set_header    Connection "upgrade";

        proxy_pass          http://127.0.0.1:764/;
        
        # define url prefix
        set                 $url_prefix rei;
        # remove url prefix to pass to backend
        rewrite             ^/rei/?(.*)$ /$1 break;
        rewrite_log         on;
        # redirect location 
        proxy_redirect      ^ /$url_prefix;
        proxy_redirect      /discover /$url_prefix/discover;
        proxy_redirect      /library /$url_prefix/library;
        proxy_redirect      /sources /$url_prefix/discover;
        proxy_redirect      /settings /$url_prefix/settings;
        proxy_redirect      /series /$url_prefix/series;
        proxy_redirect      /genres /$url_prefix/genres;
        proxy_redirect      /networks /$url_prefix/networks;
        
        # sub filters to replace hardcoded paths
        proxy_set_header    Accept-Encoding "";
        sub_filter_last_modified on;
        sub_filter_once     off;
        sub_filter_types    *;
        sub_filter          '(?!.*\.themoviedb\.org|.*\.tmdb\.org).*/discover/' '/$url_prefix/discover/';
        sub_filter          '/networks/' '/$url_prefix/networks/';
        sub_filter          '/genres/' '/$url_prefix/genres/';
        sub_filter          '/series/' '/$url_prefix/series/';
        sub_filter          '/settings/' '/$url_prefix/settings/';
        sub_filter          '/sources/' '/$url_prefix/sources/';
        sub_filter          '/library/' '/$url_prefix/library/';
        sub_filter          '"/settings' '"/$url_prefix/settings';
        sub_filter          '"/sources' '"/$url_prefix/sources';
        sub_filter          '"/library' '"/$url_prefix/library';
    }
    
    

Reiverr version 1.1.1
Nginx is on 0.0.0.0:763
Reiverr is on 0.0.0.0:764, is a served by running NODE_ENV="production" PORT=764 node build/ on a node alpine container

Error for sources,library,settings pages

i am not expert in nginx, node, this is a mix and match of my research on web and AI,