feat: Add support for more tool, standardize copilot chat service (#11560)

enterprise/app/models/copilot_message.rb

@@ -25,6 +25,7 @@ class CopilotMessage < ApplicationRecord
 
   validates :message_type, presence: true, inclusion: { in: message_types.keys }
   validates :message, presence: true
+  validate :validate_message_attributes
 
   after_create_commit :broadcast_message
 
@@ -47,4 +48,13 @@ class CopilotMessage < ApplicationRecord
   def broadcast_message
     Rails.configuration.dispatcher.dispatch(COPILOT_MESSAGE_CREATED, Time.zone.now, copilot_message: self)
   end
+
+  def validate_message_attributes
+    return if message.blank?
+
+    allowed_keys = %w[content reasoning function_name]
+    invalid_keys = message.keys - allowed_keys
+
+    errors.add(:message, "contains invalid attributes: #{invalid_keys.join(', ')}") if invalid_keys.any?
+  end
 end