- Rename and move modules.gresource.xml -> js.gresource.xml
  This reflects that new environments may require JS
  resources outside of modules/
- Move the "core" cairo, format, gettext, and signals logic
  to modules/core/ to allow reuse across environments.
- Move the "legacy" (script-based) modules to modules/script/
- Move the script-based bootstrap files to modules/script/
- Move overrides to modules/core/ as they will be reused
  across environments
- Update meson resource compilation.
- Update js.gresource.xml for new module paths.
- Update resource path references in C++.