support following symlinks

In my case, the app.py is a symlink to a file in the parent directory (long story, but there is a good reason for this). When rsconnect deploys an app, does it follow local symlinks so that the content is deployed to the server?
The reason I have symlinks is because I have many apps in the same directory (named app_basic.py, app_recipes.py, etc.) and I want to deploy the apps individually, but I think rsconnect wants them to be named app.py. So I made a directory for each with symlinks from foo/app.py to the original file, like app_basic.py.
Why are they all in the same directory? Because they share common submodules, like utils.py, chat/init.py, and so on.

When constructing the list of files to bundle we currently rely on os.path.isfile so symlinks are not followed.

Start in rsconnect/bundle.py at the os.path.isfile call around line 962, where the list of files to bundle is constructed. Trace how that list is used during deployment, then verify that a symlinked app file's target content is included in the bundle without breaking the existing file selection behavior.