me/spider ? reverse-engineered prompt

Build me a Ruby web framework for building web apps with an MVC structure.

I want models that are defined in Ruby, can work with legacy databases, support smart querying and deep loading, and avoid extra database calls when fetching related data. The view layer should use HTML style templates with variable substitution, simple conditionals, loops, reusable widgets, and template extension so one view can override another cleanly. Controllers should be light, support routing, before and after hooks, and let me expose actions in different content types. Widgets should behave like mini controllers too.

Please also include a browser side JavaScript layer that can talk to the server, reload widgets individually, and keep working even when JavaScript is off. Add YAML config, support for multiple apps, gettext based translation, and a simple way to generate and run a demo app from the command line.

Make it feel polished and practical, and look up current Ruby docs online if you need to.