feat: Ability to reply to specific tweets (#1117)

Ability to choose a specific tweet to reply to

Fixes #982
Co-authored-by: Pranav Raj S <pranav@thoughtwoot.com>

spec/factories/messages.rb

@@ -9,7 +9,7 @@ FactoryBot.define do
     account { create(:account) }
 
     after(:build) do |message|
-      message.sender ||= create(:user, account: message.account)
+      message.sender ||= message.outgoing? ? create(:user, account: message.account) : create(:contact, account: message.account)
       message.inbox ||= create(:inbox, account: message.account)
       message.conversation ||= create(:conversation, account: message.account, inbox: message.inbox)
     end

spec/lib/integrations/slack/send_on_slack_service_spec.rb

@@ -20,7 +20,7 @@ describe Integrations::Slack::SendOnSlackService do
       expect(slack_client).to receive(:chat_postMessage).with(
         channel: hook.reference_id,
         text: message.content,
-        username: "Agent: #{message.sender.name}",
+        username: "Contact: #{message.sender.name}",
         thread_ts: conversation.identifier,
         icon_url: anything
       )