refactor: email sync changes

lib/accounts/user.ex

@@ -93,8 +93,11 @@ defmodule Mv.Accounts.User do
       # complex checks that are not supported in atomic operations.
       require_atomic? false
 
-      # Sync email changes to linked member
-      change Mv.Accounts.User.Changes.SyncEmailToMember
+      # Sync email changes to linked member (User → Member)
+      # Only runs when email is being changed
+      change Mv.EmailSync.Changes.SyncUserEmailToMember do
+        where [changing(:email)]
+      end
     end
 
     create :create_user do
@@ -118,8 +121,8 @@ defmodule Mv.Accounts.User do
                on_missing: :ignore
              )
 
-      # Override member email with user email when linking
-      change Mv.Accounts.User.Changes.OverrideMemberEmailOnLink
+      # Sync user email to member when linking (User → Member)
+      change Mv.EmailSync.Changes.SyncUserEmailToMember
     end
 
     update :update_user do
@@ -147,10 +150,11 @@ defmodule Mv.Accounts.User do
                on_missing: :unrelate
              )
 
-      # Sync email changes to linked member
-      change Mv.Accounts.User.Changes.SyncEmailToMember
-      # Override member email with user email when linking
-      change Mv.Accounts.User.Changes.OverrideMemberEmailOnLink
+      # Sync email changes and handle linking (User → Member)
+      # Runs when email OR member relationship changes
+      change Mv.EmailSync.Changes.SyncUserEmailToMember do
+        where any([changing(:email), changing(:member)])
+      end
     end
 
     # Admin action for direct password changes in admin panel
@@ -200,8 +204,8 @@ defmodule Mv.Accounts.User do
         |> Ash.Changeset.change_attribute(:oidc_id, user_info["sub"] || user_info["id"])
       end
 
-      # Override member email with user email when linking (if member relationship exists)
-      change Mv.Accounts.User.Changes.OverrideMemberEmailOnLink
+      # Sync user email to member when linking (User → Member)
+      change Mv.EmailSync.Changes.SyncUserEmailToMember
     end
   end
 
@@ -281,9 +285,8 @@ defmodule Mv.Accounts.User do
     # User.email is the source of truth - when a link is established, member.email
     # is overridden to match user.email. Subsequent changes to either email will
     # sync to the other resource.
-    # See: Mv.Accounts.User.Changes.SyncEmailToMember
-    #      Mv.Accounts.User.Changes.OverrideMemberEmailOnLink
-    #      Mv.Membership.Member.Changes.SyncEmailToUser
+    # See: Mv.EmailSync.Changes.SyncUserEmailToMember
+    #      Mv.EmailSync.Changes.SyncMemberEmailToUser
     attribute :email, :ci_string do
       allow_nil? false
       public? true