Add @jbrowse/react-app embedded component

[cmdcolin]

This is a proof of concept to show we can embed the whole jbrowse-web app as a react component, which I call @jbrowse/react-app

There are still many things that need improving, but it does work at a base level.

The storybook works as a good live demo of this. Most of the stories are not wired up to automatically load a particular view yet, but can be clicked anyways
https://jbrowse.org/storybook/app/main_webapp_component/

Right now, this essentially copies and pastes the entire jbrowse-web src directory, which is a fairly large code duplication, but as we have seen with desktop, it may be that embedded has significantly different needs than web, so having it separate (for now) could be ok

[codecov]

Codecov Report

Merging #3531 (d1e609a) into main (7c1ce5c) will decrease coverage by 0.36%.
The diff coverage is 38.10%.

@@            Coverage Diff             @@
##             main    #3531      +/-   ##
==========================================
- Coverage   64.66%   64.30%   -0.36%     
==========================================
  Files         945      961      +16     
  Lines       29786    29959     +173     
  Branches     7171     7190      +19     
==========================================
+ Hits        19261    19266       +5     
- Misses      10361    10529     +168     
  Partials      164      164              

Impacted Files	Coverage Δ
packages/app-core/src/ui/App/App.tsx	96.55% <ø> (ø)
packages/app-core/src/ui/App/AppToolbar.tsx	53.84% <0.00%> (ø)
...ckages/product-core/src/RootModel/BaseRootModel.ts	32.00% <ø> (ø)
...owse-react-app/src/JBrowseWebApp/JBrowseWebApp.tsx	0.00% <0.00%> (ø)
...wse-react-app/src/components/PreferencesDialog.tsx	0.00% <0.00%> (ø)
products/jbrowse-react-app/src/createModel.ts	0.00% <0.00%> (ø)
products/jbrowse-react-app/src/createViewState.ts	0.00% <0.00%> (ø)
products/jbrowse-react-app/src/jbrowseConfig.ts	0.00% <0.00%> (ø)
products/jbrowse-react-app/src/loadPlugins.ts	0.00% <0.00%> (ø)
products/jbrowse-react-app/src/rpc.worker.ts	0.00% <0.00%> (ø)
... and 14 more

... and 2 files with indirect coverage changes

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[cmdcolin]

we could consider merging this as-is, but mark it as private:true until ready to publish. I'll mark this as ready for review

[cmdcolin]

now does not attempt to store session data in sessionStorage or localStorage, nor does it have undo/redo, or theme changing...could try to modularize those out into an optional mixins and document how to add them in a storybook but it may be reasonable default to leave our be default