If HTTP signature is wrong and webfinger cache is stale, retry with resolve (#5129)

If the signature could not be verified and the webfinger of the account
was last retrieved longer than the cache period, try re-resolving the
account and then attempting to verify the signature again

app/models/account.rb

@@ -137,6 +137,15 @@ class Account < ApplicationRecord
     subscription_expires_at.present?
   end
 
+  def possibly_stale?
+    last_webfingered_at.nil? || last_webfingered_at <= 1.day.ago
+  end
+
+  def refresh!
+    return if local?
+    ResolveRemoteAccountService.new.call(acct)
+  end
+
   def keypair
     @keypair ||= OpenSSL::PKey::RSA.new(private_key || public_key)
   end