Apply slug immediately for never-published nodes

staged_slug existed to protect a live public URL from changing until
an editor explicitly publishes - correct once a node has a head, but
nodes_controller#update wrote to it unconditionally, so a brand-new
node being renamed before its first-ever publish showed a stale slug
in previews (e.g. nodes#new's resulting-path preview) that silently
diverged from what would actually go live.

Node#staged_slug= now applies directly to slug when head is blank -
nothing is live yet, so there's nothing to protect. Once head is
present, defers to staged_slug exactly as before. Verified both paths
directly: a never-published node's slug now updates immediately, and
an already-published node's rename still stays deferred until the
next publish, unchanged from existing behavior.

1 files changed, 8 insertions, 0 deletions

diff --git a/app/models/node.rb b/app/models/node.rb
index ba94e2a..2177f15 100644
--- a/app/models/node.rb
+++ b/app/models/node.rb
@@ -94,6 +94,14 @@ class Node < ApplicationRecord
     self.draft.reload
   end
 
+  def staged_slug=(value)
+    if head.blank?
+      self.slug = value
+    else
+      super
+    end
+  end
+
   def publish_draft!
     # Return nil if nothing to publish and no staged changes
     return nil unless self.draft || staged_slug || staged_parent_id