chore(sidekiq): log ActiveJob class and job_id on dequeue (#12704)

## Context

Sidekiq logs only showed the Sidekiq wrapper class and JID, which wasn’t
helpful when debugging ActiveJobs.

## Changes

- Updated `ChatwootDequeuedLogger` to log the actual `ActiveJob class`
and `job_id` instead of the generic Sidekiq wrapper and JID.

> Example
> ```
> Dequeued ActionMailer::MailDeliveryJob
123e4567-e89b-12d3-a456-426614174000 from default
> ```

- Remove sidekiq worker and unify everything to `ActiveJob`

spec/jobs/conversation_reply_email_job_spec.rb

@@ -0,0 +1,33 @@
+require 'rails_helper'
+
+RSpec.describe ConversationReplyEmailJob, type: :job do
+  let(:conversation) { create(:conversation) }
+  let(:mailer) { double }
+  let(:mailer_action) { double }
+
+  before do
+    allow(Conversation).to receive(:find).and_return(conversation)
+    allow(ConversationReplyMailer).to receive(:with).and_return(mailer)
+    allow(mailer).to receive(:reply_with_summary).and_return(mailer_action)
+    allow(mailer).to receive(:reply_without_summary).and_return(mailer_action)
+    allow(mailer_action).to receive(:deliver_later).and_return(true)
+  end
+
+  it 'enqueues on mailers queue' do
+    ActiveJob::Base.queue_adapter = :test
+    expect do
+      described_class.perform_later(conversation.id, 123)
+    end.to have_enqueued_job(described_class).on_queue('mailers')
+  end
+
+  it 'calls reply_with_summary when last incoming message was not email' do
+    described_class.perform_now(conversation.id, 123)
+    expect(mailer).to have_received(:reply_with_summary)
+  end
+
+  it 'calls reply_without_summary when last incoming message was email' do
+    create(:message, conversation: conversation, message_type: :incoming, content_type: 'incoming_email')
+    described_class.perform_now(conversation.id, 123)
+    expect(mailer).to have_received(:reply_without_summary)
+  end
+end