Update Shinylive.io to use Express where possible

[gshotwell]

The shinylive.io has been superceded in many cases by the component gallery so we can remove a few things. It is substantially easier to use shiny express in the web editor so where possible we should use Express on this site instead of offering an Expres/Core option. The Template gallery will have Express and Core apps side-by-side.

Remove

• Input apps in favour of Component Gallery
• Output apps in favour of Component Gallery
• Layout apps in favour of Layout Gallery
• Camera (seems to be a very niche use case)

Translate

• Basic App
• App with plo9
• CPU Info
• Regularization
• Multiple source files
• Read local CSV
• File upload
• File download
• Dynamically inserting UI
• Updating UI
• Fetch data from web API
• ipywidgets (wait for shinywidgets update)
• plotly (wait for shinywidgets update)
• reactive decorator
• reactive effect
• reactive calc
• reactive value
• Extra packages

Move to Core section

• Modules
• Basic plot interaction
• Interactively excluding data
• Orbit Simulation (uses modules)
• Worldle (Too complicated for express)
• Static content

Replace

• Map with template/map (wait for shinywidgets)

[gshotwell]

This was closed in a number of PRs, the last of which is here posit-dev/shinylive#99