Convert App to TypeScript

[Zyie]

Description of change

Converts app package to TypeScript.

The main changes are:

• Moved IApplicationOptions out of global.d.ts and now extends `IRendererOptionsAuto
• Created IApplicationPlugin interface

There is a change that will need to be made once CanvasRenderer is converted. I've documented this with TODO's, but essentially there is some unnecessary casting happening to make TypeScript happy.

Pre-Merge Checklist

• Documentation is changed or added
• Lint process passed (npm run lint)
• Tests passed (npm run test)

[bigtimebuddy]

Looks good, just the issue with the import in TickerPlugin

[codecov-io]

Codecov Report

Merging #6376 into dev will decrease coverage by 0.77%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##              dev    #6376      +/-   ##
==========================================
- Coverage   74.85%   74.08%   -0.78%     
==========================================
  Files          83       82       -1     
  Lines        4773     4569     -204     
==========================================
- Hits         3573     3385     -188     
+ Misses       1200     1184      -16

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