In the early days of RWT, we used to package and distribute debian packages with the RWT JavaScript sources. After lots of consideration, we pulled away from this practice in lieu of more convention web programming standards.
In particular, typically JavaScript sources are served via some web server. When installing a debian package, it is unclear where a JavaScript file should be "installed" since web directors are custom to the server at hand. Furthermore, the ROS build system itself is not intended for JavaScript at all. Catkin, which is really an extension of CMake, is not really a tool used for JavaSript (we instead use Grunt to manage all of our "building" and Travis CI to run tests and integrity checks). The doc builders are also unaware of how to handle JSDoc.
The main reason, though, is that releases of JavaScript files are not made on a per-computer basis (e.g., installing a local copy for any developer or user). Instead, Content Distribution Networks (or CDNs), are used and is what we use to manage our releases. Links to these are listed on the wiki pages as well as in each projects readme: http://wiki.ros.org/roslibjs#CDN_Releases
