chore: support for APMs (#2874)

Add the support for Newrelic and Datadog.
ref: https://www.chatwoot.com/docs/self-hosted/monitoring/apm-and-error-monitoring

fixes: #2861

config/initializers/datadog.rb

@@ -0,0 +1,6 @@
+if ENV['DD_TRACE_AGENT_URL']
+  Datadog.configure do |c|
+    # This will activate auto-instrumentation for Rails
+    c.use :rails
+  end
+end

config/initializers/sentry.rb

@@ -1,4 +1,6 @@
-Sentry.init do |config|
-  config.dsn = ENV['SENTRY_DSN']
-  config.enabled_environments = %w[staging production]
+if ENV['SENTRY_DSN']
+  Sentry.init do |config|
+    config.dsn = ENV['SENTRY_DSN']
+    config.enabled_environments = %w[staging production]
+  end
 end