feat(llm): include conversation created time in LLM text format

app/services/llm_formatter/conversation_llm_formatter.rb

@@ -3,6 +3,7 @@ class LlmFormatter::ConversationLlmFormatter < LlmFormatter::DefaultLlmFormatter
     sections = []
     sections << "Conversation ID: ##{@record.display_id}"
     sections << "Channel: #{@record.inbox.channel.name}"
+    sections << "Created At: #{@record.created_at}"
     sections << 'Message History:'
     sections << if @record.messages.any?
                   build_messages(config)

spec/services/llm_formatter/conversation_llm_formatter_spec.rb

@@ -11,6 +11,7 @@ RSpec.describe LlmFormatter::ConversationLlmFormatter do
         expected_output = [
           "Conversation ID: ##{conversation.display_id}",
           "Channel: #{conversation.inbox.channel.name}",
+          "Created At: #{conversation.created_at}",
           'Message History:',
           'No messages in this conversation'
         ].join("\n")
@@ -46,6 +47,7 @@ RSpec.describe LlmFormatter::ConversationLlmFormatter do
         expected_output = [
           "Conversation ID: ##{conversation.display_id}",
           "Channel: #{conversation.inbox.channel.name}",
+          "Created At: #{conversation.created_at}",
           'Message History:',
           'User: Hello, I need help',
           'Bot: Thanks for reaching out, an agent will reach out to you soon',
@@ -62,6 +64,7 @@ RSpec.describe LlmFormatter::ConversationLlmFormatter do
         expected_output = [
           "Conversation ID: ##{conversation.display_id}",
           "Channel: #{conversation.inbox.channel.name}",
+          "Created At: #{conversation.created_at}",
           'Message History:',
           'No messages in this conversation',
           "Contact Details: #{conversation.contact.to_llm_text}"
@@ -86,6 +89,7 @@ RSpec.describe LlmFormatter::ConversationLlmFormatter do
         expected_output = [
           "Conversation ID: ##{conversation.display_id}",
           "Channel: #{conversation.inbox.channel.name}",
+          "Created At: #{conversation.created_at}",
           'Message History:',
           'No messages in this conversation',
           'Conversation Attributes:',