feat: custom branding (#112)

* add first concept

* remove setup status

* split config page in multiple components

* add custom branding docs

* add test email button

* fix invalid email from header

* add migration

* mount images to host

* update docs

* remove unused endpoint

* run formatter

backend/src/auth/guard/jwt.guard.ts

@@ -11,7 +11,7 @@ export class JwtGuard extends AuthGuard("jwt") {
     try {
       return (await super.canActivate(context)) as boolean;
     } catch {
-      return this.config.get("ALLOW_UNAUTHENTICATED_SHARES");
+      return this.config.get("share.allowUnauthenticatedShares");
     }
   }
 }