Consolidate script editors, add analysis.R

[WardBrian]

I decided to open this as a replacement to PR #155 rather than just pushing to that branch because I did a bunch of code moves.

This PR:

• Adds two new components, ScriptEditor and its big brother, PlottingScriptEditor. These are the basis of the data and analysis tabs.
• Refactored the existing tabs to share as much code as is reasonable, and use those components
• Reorganize the folder structure of this code (everything that touches webr/pyodide now entirely lives under app/Scripting) and move any large R/Python code chunks out of strings and into their own dedicate files.
• Add the analysis.R window, with the loading code for the draws based on posterior.

Only this final bullet point changes any of the functionality, the rest is just tech debt cleanup.

Closes #106
Closes #58

[magland]

Very Cool!

Before I start reading the code, I wanted to test to see if everything is working. One thing I noticed (I think it was introduced in this PR). When I run the python data generation script it always needs to reload pyodide. Is the worker getting terminated?

data.R does not have this problem.

analysis.py and analysis.R also do not have this problem.

[WardBrian]

@magland I observe the behavior you are describing on the current main at https://stan-playground.flatironinstitute.org/, so I don't think it originates here. I have a hunch about where it would come from, let me see if I'm correct.

Otherwise, another point in favor of #142, possibly

[WardBrian]

@magland I believe it is fixed. Basically, the onData part of the callback was changing after every run, since it depended on the data, so it re-loaded the usePyodide hook.

[magland]

Just a few minor comments. We should merge this soon because there are so many changes and renames.

[WardBrian]

@magland done, and I agree I'd prefer to merge this before too much else just due to conflicts. I'd still appreciate if @jsoules could take a look, since some of the consolidation was a request of his

[jsoules]

I think this looks fine. There's a couple minor things that might be slightly cleaner, but I'd also be happy to just merge as is.