fix: inconsistent OpenAI cache interface (#10009)

Signed-off-by: Shivam Mishra <scm.mymail@gmail.com>
Co-authored-by: Muhsin Keloth <muhsinkeramam@gmail.com>

app/controllers/api/v1/accounts/integrations/hooks_controller.rb

@@ -12,7 +12,12 @@ class Api::V1::Accounts::Integrations::HooksController < Api::V1::Accounts::Base
 
   def process_event
     response = @hook.process_event(params[:event])
-    if response[:error]
+
+    # for cases like an invalid event, or when conversation does not have enough messages
+    # for a label suggestion, the response is nil
+    if response.nil?
+      render json: { message: nil }
+    elsif response[:error]
       render json: { error: response[:error] }, status: :unprocessable_entity
     else
       render json: { message: response[:message] }