chore: mark conversation notifications as read on visit (#13906)

app/controllers/api/v1/accounts/conversations_controller.rb

@@ -116,6 +116,8 @@ class Api::V1::Accounts::ConversationsController < Api::V1::Accounts::BaseContro
     # High-traffic accounts generate excessive DB writes when agents frequently switch between conversations.
     # Throttle last_seen updates to once per hour when there are no unread messages to reduce DB load.
     # Always update immediately if there are unread messages to maintain accurate read/unread state.
+    # Visiting a conversation should clear any unread inbox notifications for this conversation.
+    Notification::MarkConversationReadService.new(user: Current.user, account: Current.account, conversation: @conversation).perform
     return update_last_seen_on_conversation(DateTime.now.utc, true) if assignee? && @conversation.assignee_unread_messages.any?
     return update_last_seen_on_conversation(DateTime.now.utc, false) if !assignee? && @conversation.unread_messages.any?
 

app/services/notification/mark_conversation_read_service.rb

@@ -0,0 +1,25 @@
+class Notification::MarkConversationReadService
+  pattr_initialize [:user!, :account!, :conversation!]
+
+  def perform
+    return unless user.is_a?(User)
+
+    notifications.find_each do |notification|
+      notification.update!(read_at: read_at)
+    end
+  end
+
+  private
+
+  def notifications
+    user.notifications.where(
+      account: account,
+      primary_actor: conversation,
+      read_at: nil
+    )
+  end
+
+  def read_at
+    @read_at ||= Time.current
+  end
+end