[Enhancement] allow object properties named "$"

[Andreas Rozek]

$ is a common name for object properties, particularly in browser environments (the best-known example should be jQuery)

While it is a nice idea to access object property signals using $name or array element signals using $[index], it should remain possible to use $ by itself as the name of an object (not an array) property - and $$ as the name for its related signal.

The required changes should be trivial (see my own fork of your repository)

[Luis Herranz]

I've been thinking about this and for the moment I'm not going to add it. It increases the bundle size to solve a very rare case that is not common and can be easily avoided by the user.