Fix Rails main compatibility: replace removed find_template with find (#341)

* Initial plan

* Fix: replace removed find_template with find in ActionView::LookupContext

---------

Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>

Author: Copilot

lib/active_agent/concerns/view.rb

@@ -142,7 +142,7 @@ def view_render_template(template_name, strict: false, formats: nil, **locals)
 
       return if !strict && !lookup_context.exists?(template_name, _prefixes, false, [], **options)
 
-      template = lookup_context.find_template(template_name, _prefixes, false, [], **options)
+      template = lookup_context.find(template_name, _prefixes, false, [], **options)
 
       render_to_string(template: template.virtual_path, locals:, layout: false).chomp.presence
     end