feat(ee): Add Captain features (#10665)

Migration Guide: https://chwt.app/v4/migration

This PR imports all the work related to Captain into the EE codebase. Captain represents the AI-based features in Chatwoot and includes the following key components:

- Assistant: An assistant has a persona, the product it would be trained on. At the moment, the data at which it is trained is from websites. Future integrations on Notion documents, PDF etc. This PR enables connecting an assistant to an inbox. The assistant would run the conversation every time before transferring it to an agent.
- Copilot for Agents: When an agent is supporting a customer, we will be able to offer additional help to lookup some data or fetch information from integrations etc via copilot.
- Conversation FAQ generator: When a conversation is resolved, the Captain integration would identify questions which were not in the knowledge base.
- CRM memory: Learns from the conversations and identifies important information about the contact.

---------

Co-authored-by: Vishnu Narayanan <vishnu@chatwoot.com>
Co-authored-by: Sojan <sojan@pepalo.com>
Co-authored-by: iamsivin <iamsivin@gmail.com>
Co-authored-by: Sivin Varghese <64252451+iamsivin@users.noreply.github.com>

enterprise/app/jobs/captain/conversation/response_builder_job.rb

@@ -0,0 +1,90 @@
+class Captain::Conversation::ResponseBuilderJob < ApplicationJob
+  MAX_MESSAGE_LENGTH = 10_000
+
+  def perform(conversation, assistant)
+    @conversation = conversation
+    @assistant = assistant
+
+    ActiveRecord::Base.transaction do
+      generate_and_process_response
+    end
+  rescue StandardError => e
+    handle_error(e)
+  end
+
+  private
+
+  delegate :account, :inbox, to: :@conversation
+
+  def generate_and_process_response
+    @response = Captain::Llm::AssistantChatService.new(assistant: @assistant).generate_response(
+      @conversation.messages.incoming.last.content,
+      collect_previous_messages
+    )
+
+    return process_action('handoff') if handoff_requested?
+
+    create_messages
+  end
+
+  def collect_previous_messages
+    @conversation
+      .messages
+      .where(message_type: [:incoming, :outgoing])
+      .where(private: false)
+      .map do |message|
+        {
+          content: message.content,
+          role: determine_role(message)
+        }
+      end
+  end
+
+  def determine_role(message)
+    message.message_type == 'incoming' ? 'user' : 'system'
+  end
+
+  def handoff_requested?
+    @response['response'] == 'conversation_handoff'
+  end
+
+  def process_action(action)
+    case action
+    when 'handoff'
+      create_handoff_message
+      @conversation.bot_handoff!
+    end
+  end
+
+  def create_handoff_message
+    create_outgoing_message('Transferring to another agent for further assistance.')
+  end
+
+  def create_messages
+    validate_message_content!(@response['response'])
+    create_outgoing_message(@response['response'])
+  end
+
+  def validate_message_content!(content)
+    raise ArgumentError, 'Message content cannot be blank' if content.blank?
+  end
+
+  def create_outgoing_message(message_content)
+    @conversation.messages.create!(
+      message_type: :outgoing,
+      account_id: account.id,
+      inbox_id: inbox.id,
+      content: message_content
+    )
+  end
+
+  def handle_error(error)
+    log_error(error)
+    process_action('handoff')
+    true
+  end
+
+  def log_error(error)
+    ChatwootExceptionTracker.new(error, account: account).capture_exception
+  end
+end