refactor: inline the retried-reference branch

`retried_reference` wrapped one branch with one caller. `retry` shows
the branch and `enqueue_retry` keeps only the enqueue, which the branch
needs a name for.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

Author: cardmagic

lib/solid_objects/dead_letter_manager.rb

@@ -14,7 +14,11 @@ def retry(dead_letter_id, authorization_context: nil)
       actor = AdministrationAudit.identity(authorization_context)
       SolidObjects.database_adapter.transaction do
         dead_letter = DeadLetter.find(dead_letter_id)
-        reference = retried_reference(dead_letter)
+        reference = if dead_letter.retried_message_id
+          MessageReference.from_message(Message.find(dead_letter.retried_message_id))
+        else
+          enqueue_retry(dead_letter)
+        end
         AdministrationAudit.record(
           action: "dead_letter.retry",
           kind: "message",
@@ -48,11 +52,7 @@ def broadcasts
     private
 
     # @rbs (DeadLetter) -> MessageReference
-    def retried_reference(dead_letter)
-      if dead_letter.retried_message_id
-        return MessageReference.from_message(Message.find(dead_letter.retried_message_id))
-      end
-
+    def enqueue_retry(dead_letter)
       message_reference = Mailbox.new.enqueue(
         reference: Reference.new(
           actor_type: dead_letter.actor_type,

sig/generated/lib/solid_objects/dead_letter_manager.rbs

@@ -17,7 +17,7 @@ module SolidObjects
     private
 
     # @rbs (DeadLetter) -> MessageReference
-    def retried_reference: (DeadLetter) -> MessageReference
+    def enqueue_retry: (DeadLetter) -> MessageReference
 
     # @rbs (Symbol, authorization_context: untyped, ?dead_letter_id: Integer?) -> void
     def authorize!: (Symbol, authorization_context: untyped, ?dead_letter_id: Integer?) -> void