chore: Refactor MarkMessagesAsReadJob based on conversation id and time stamp (#8217)

- Mark all messages as read by providing the conversation ID and timestamp.
- For Instagram, ensure all previous messages that weren't marked as failed are now marked as read. This is because the read events are only triggered for the most recent message and not for any previous ones.

spec/controllers/api/v1/widget/conversations_controller_spec.rb

@@ -168,9 +168,12 @@ RSpec.describe '/api/v1/widget/conversations/toggle_typing', type: :request do
   describe 'POST /api/v1/widget/conversations/update_last_seen' do
     context 'with a conversation' do
       it 'returns the correct conversation params' do
+        current_time = DateTime.now.utc
+        allow(DateTime).to receive(:now).and_return(current_time)
+
         allow(Rails.configuration.dispatcher).to receive(:dispatch)
         expect(conversation.contact_last_seen_at).to be_nil
-        expect(Conversations::MarkMessagesAsReadJob).to receive(:perform_later).with(conversation)
+        expect(Conversations::MarkMessagesAsReadJob).to receive(:perform_later).with(conversation.id, current_time)
 
         post '/api/v1/widget/conversations/update_last_seen',
              headers: { 'X-Auth-Token' => token },