feat(settings): add settings for custom DNS servers and IPv4 resolution first (#1266)

* feat(settings): add settings for custom DNS servers and IPv4 resolution first

This PR adds settings to change the DNS servers Jellyseerr uses and to force Jellyseerr to resolve
DNS queries using IPv4 first. These settings aim to make it easier for less experienced users to fix
network errors related to DNS resolution.

* style: fix missing newline

server/lib/settings/index.ts

@@ -132,6 +132,8 @@ export interface MainSettings {
   mediaServerType: number;
   partialRequestsEnabled: boolean;
   enableSpecialEpisodes: boolean;
+  forceIpv4First: boolean;
+  dnsServers: string;
   locale: string;
   proxy: ProxySettings;
 }
@@ -346,6 +348,8 @@ class Settings {
         mediaServerType: MediaServerType.NOT_CONFIGURED,
         partialRequestsEnabled: true,
         enableSpecialEpisodes: false,
+        forceIpv4First: false,
+        dnsServers: '',
         locale: 'en',
         proxy: {
           enabled: false,