Detect assembly loading error and encapsulate error instead of failing at app level

[cmdcolin]

This PR allows detecting that an assembly failed to load for either the case of

(a) a defaultSession loads a view who has a displayedRegion assembly that fails e.g. 404
(b) browsing the import form and selecting an assembly gives an error e.g. 404

See #2235

The volvox demo data has a "volvox404" assembly added that is always a 404. To test, you can also generate other errors by turning off network in chrome or inserting a throw into the sequence adapter's getRegions function or similar.

This results in a couple places where we have to be careful to clear the error state. There is the view model's error state, and there is the import form components error state. The import form components error state is initialized with the model's error state, and import form onSubmit clears the model's error state

This is also for the LGV only, and if we want to put it into other parts of the app, we may need to perform more effort, or create some better abstractions.

screenshot showing the 404 from volvox

[cmdcolin]

Target branch is #2188 but probably doesn't necessarily have to be

[codecov]

Codecov Report

Merging #2236 (7bf1a16) into main (2c74146) will increase coverage by 0.03%.
The diff coverage is 71.75%.

@@            Coverage Diff             @@
##             main    #2236      +/-   ##
==========================================
+ Coverage   62.98%   63.01%   +0.03%     
==========================================
  Files         485      488       +3     
  Lines       22716    22760      +44     
  Branches     5159     5170      +11     
==========================================
+ Hits        14308    14343      +35     
- Misses       8138     8147       +9     
  Partials      270      270              

Impacted Files	Coverage Δ
...r-view/src/CircularView/components/CircularView.js	94.44% <ø> (+3.53%)	⬆️
...ew/src/LinearSyntenyView/components/ImportForm.tsx	0.00% <0.00%> (ø)
...nce/src/IndexedFastaAdapter/IndexedFastaAdapter.ts	81.25% <0.00%> (+5.57%)	⬆️
packages/core/assemblyManager/assemblyManager.ts	59.21% <42.85%> (-0.79%)	⬇️
packages/core/assemblyManager/assembly.ts	86.66% <57.14%> (ø)
...iew/src/LinearGenomeView/components/ImportForm.tsx	60.86% <60.97%> (-0.33%)	⬇️
plugins/dotplot-view/src/DotplotView/model.ts	65.26% <63.74%> (+2.76%)	⬆️
...ar-view/src/CircularView/components/ImportForm.tsx	73.07% <73.07%> (ø)
...lot-view/src/DotplotView/components/ImportForm.tsx	89.28% <82.35%> (+5.28%)	⬆️
...s/dotplot-view/src/DotplotView/components/Axes.tsx	86.53% <86.53%> (ø)
... and 15 more

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