Feature/reapply syntax highlighting onColorscheme autocmd

[akinsho]

This PR fixes the issue where setting your colorscheme e.g. as might happen when you source your vim config causes the syntax highlighting to be removed.
The issue is/was that vim re-applied the vim colorscheme highlights ignoring oni's highlighting and oni having cached a record of the highlighted lines believes that everything is still highlighted.

This adds an action to the highlighter that is triggered on the colorscheme autocommand which causes oni to re apply its textmate based highlighting.

Outstanding

• Currently we call the highlight command for each line/token that requires highlighting, this means we dispatch 100s of atomicCalls to neovim so that when we currently trigger the colorscheme autocmd there is a block for about half a second where a user cannot interact with Oni. ---> 😢 😞 Resolved this by only passing the visible tokens to the highlight function so only those are added to the highlight case when a page redraws

[codecov]

Codecov Report

Merging #2565 into master will decrease coverage by <.01%.
The diff coverage is 59.15%.

@@            Coverage Diff            @@
##           master   #2565      +/-   ##
=========================================
- Coverage    45.3%   45.3%   -0.01%     
=========================================
  Files         361     361              
  Lines       14571   14589      +18     
  Branches     1912    1916       +4     
=========================================
+ Hits         6601    6609       +8     
- Misses       7746    7753       +7     
- Partials      224     227       +3

Impacted Files	Coverage Δ
browser/src/Editor/BufferHighlights.ts	16.66% <ø> (ø)	⬆️
...es/SyntaxHighlighting/SyntaxHighlightingReducer.ts	30.95% <0%> (-4.19%)	⬇️
browser/src/Editor/NeovimEditor/NeovimEditor.tsx	8.62% <0%> (ø)	⬆️
browser/src/Utility.ts	46.32% <0%> (-0.7%)	⬇️
...ices/SyntaxHighlighting/SyntaxHighlightingStore.ts	25.86% <0%> (-0.46%)	⬇️
browser/src/neovim/NeovimInstance.ts	5.47% <0%> (ø)	⬆️
...ser/src/Services/SyntaxHighlighting/TokenScorer.ts	97.22% <100%> (ø)	⬆️
...Services/SyntaxHighlighting/TokenThemeProvider.tsx	90.62% <100%> (ø)	⬆️
.../Services/SyntaxHighlighting/SyntaxHighlighting.ts	22.91% <25%> (-1%)	⬇️
browser/src/Services/TokenColors.ts	59.57% <72.72%> (+2.43%)	⬆️
... and 2 more

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