feat: setup captain limits (#10713)

This pull request introduces several changes to implement and manage
usage limits for the Captain AI service. The key changes include adding
configuration for plan limits, updating error messages, modifying
controllers and models to handle usage limits, and updating tests to
ensure the new functionality works correctly.

## Implementation Checklist

- [x] Ability to configure captain limits per check
- [x] Update response for `usage_limits` to include captain limits
- [x] Methods to increment or reset captain responses limits in the
`limits` column for the `Account` model
- [x] Check documents limit using a count query
- [x] Ensure Captain hand-off if a limit is reached
- [x] Ensure limits are enforced for Copilot Chat
- [x] Ensure limits are reset when stripe webhook comes in 
- [x] Increment usage for FAQ generation and Contact notes
- [x] Ensure documents limit is enforced

These changes ensure that the Captain AI service operates within the defined usage limits for different subscription plans, providing appropriate error messages and handling when limits are exceeded.

enterprise/app/services/captain/copilot/chat_service.rb

@@ -15,7 +15,11 @@ class Captain::Copilot::ChatService < Captain::Llm::BaseOpenAiService
 
   def generate_response(input)
     @messages << { role: 'user', content: input } if input.present?
-    request_chat_completion
+    response = request_chat_completion
+    Rails.logger.info("[CAPTAIN][CopilotChatService] Incrementing response usage for #{@assistant.account.id}")
+    @assistant.account.increment_response_usage
+
+    response
   end
 
   private

enterprise/app/services/enterprise/billing/handle_stripe_event_service.rb

@@ -22,6 +22,7 @@ class Enterprise::Billing::HandleStripeEventService
     update_account_attributes(subscription, plan)
 
     change_plan_features
+    reset_captain_usage
   end
 
   def update_account_attributes(subscription, plan)
@@ -56,6 +57,10 @@ class Enterprise::Billing::HandleStripeEventService
     account.save!
   end
 
+  def reset_captain_usage
+    account.reset_response_usage
+  end
+
   def ensure_event_context(event)
     @event = event
   end

enterprise/app/services/enterprise/message_templates/hook_execution_service.rb

@@ -2,6 +2,7 @@ module Enterprise::MessageTemplates::HookExecutionService
   def trigger_templates
     super
     return unless should_process_captain_response?
+    return perform_handoff unless inbox.captain_active?
 
     Captain::Conversation::ResponseBuilderJob.perform_later(
       conversation,
@@ -12,4 +13,17 @@ module Enterprise::MessageTemplates::HookExecutionService
   def should_process_captain_response?
     conversation.pending? && message.incoming? && inbox.captain_assistant.present?
   end
+
+  def perform_handoff
+    return unless conversation.pending?
+
+    Rails.logger.info("Captain limit exceeded, performing handoff mid-conversation for conversation: #{conversation.id}")
+    conversation.messages.create!(
+      message_type: :outgoing,
+      account_id: conversation.account.id,
+      inbox_id: conversation.inbox.id,
+      content: 'Transferring to another agent for further assistance.'
+    )
+    conversation.bot_handoff!
+  end
 end