feat: search documentation tool for reply suggestions (#13340)

Co-authored-by: Shivam Mishra <scm.mymail@gmail.com>

lib/captain/tool_instrumentation.rb

@@ -0,0 +1,48 @@
+module Captain::ToolInstrumentation
+  extend ActiveSupport::Concern
+
+  private
+
+  # Custom instrumentation for tool flows - outputs just the message (not full hash)
+  def instrument_tool_session(params)
+    return yield unless ChatwootApp.otel_enabled?
+
+    response = nil
+    executed = false
+    tracer.in_span(params[:span_name]) do |span|
+      span.set_attribute('langfuse.user.id', params[:account_id].to_s) if params[:account_id]
+      span.set_attribute('langfuse.tags', [params[:feature_name]].to_json)
+      span.set_attribute('langfuse.observation.input', params[:messages].to_json)
+
+      response = yield
+      executed = true
+
+      # Output just the message for cleaner Langfuse display
+      span.set_attribute('langfuse.observation.output', response[:message] || response.to_json)
+    end
+    response
+  rescue StandardError => e
+    ChatwootExceptionTracker.new(e, account: account).capture_exception
+    executed ? response : yield
+  end
+
+  def record_generation(chat, message, model)
+    return unless ChatwootApp.otel_enabled?
+    return unless message.respond_to?(:role) && message.role.to_s == 'assistant'
+
+    tracer.in_span("llm.#{event_name}.generation") do |span|
+      span.set_attribute('gen_ai.system', 'openai')
+      span.set_attribute('gen_ai.request.model', model)
+      span.set_attribute('gen_ai.usage.input_tokens', message.input_tokens)
+      span.set_attribute('gen_ai.usage.output_tokens', message.output_tokens) if message.respond_to?(:output_tokens)
+      span.set_attribute('langfuse.observation.input', format_chat_messages(chat))
+      span.set_attribute('langfuse.observation.output', message.content.to_s) if message.respond_to?(:content)
+    end
+  rescue StandardError => e
+    Rails.logger.warn "Failed to record generation: #{e.message}"
+  end
+
+  def format_chat_messages(chat)
+    chat.messages[0...-1].map { |m| { role: m.role.to_s, content: m.content.to_s } }.to_json
+  end
+end