Shinylive

* Updated to Shinylive web assets 0.3.0.

* Updated to Shinylive web assets 0.2.8.

* Updated to Shinylive web assets 0.2.7.

* Updated to Shinylive web assets 0.2.6.

* Added support for packages which are listed in `requirements.txt` and are part of the Pyodide distribution, but are not `import`ed in the code, and are soft dependencies of `import`ed packages (they are optionally loaded, as opposed to hard dependencies which are always loaded). (25)

* Added `shinylive url encode` and `shinylive url decode` commands to encode local apps into a [shinylive.io](https://shinylive.io) URL or decode a [shinylive.io](https://shinylive.io) URL into local files. These commands are accompanied by `url_encode()` and `url_decode()` functions for programmatic use. They are supported by the new `ShinyliveIoApp` class which provides methods to get the app URL, save the app locally, or create a [Shinylive quarto chunk](https://quarto-ext.github.io/shinylive/) from the app's files. (#20, 23)

* Updated to Shinylive web assets 0.2.5.