auth check endpoint

Author: ornicar

app/controllers/Auth.scala

@@ -487,6 +487,10 @@ final class Auth(env: Env, accountC: => Account) extends LilaController(env):
         Firewall:
           consumingToken(token) { authenticateUser(_, remember = true, pwned = IsPwned.No) }
 
+  def check = OpenOrScoped() { ctx ?=>
+    if ctx.isAuth then NoContent else Unauthorized
+  }
+
   private def consumingToken(token: String)(f: UserModel => Fu[Result])(using Context) =
     env.security.loginToken
       .consume(token)

conf/routes

@@ -584,6 +584,7 @@ POST  /auth/token/:token               controllers.Auth.loginWithTokenPost(token
 GET   /auth/magic-link                 controllers.Auth.magicLink
 POST  /auth/magic-link/send            controllers.Auth.magicLinkApply
 GET   /auth/magic-link/sent            controllers.Auth.magicLinkSent
+GET   /auth/check                      controllers.Auth.check
 
 # Mod
 POST  /mod/:username/alt/:v            controllers.Mod.alt(username: UserStr, v: Boolean)