Add spell-checker

[mark-wiemer]

Overall, no need to be strict here about American vs British English or including variable names in a dict vs ignoring them each time they come up. Instead, let's focus on integrating an automated check that works so devs can quickly scan files and publish them with confidence.

• CI fails if words are marked as spelled incorrectly
• Contributors can easily update the list of known words
• Contributors can easily ignore entire files if they want to
• Contributors can easily identify words marked as spelled incorrectly via their IDE as a standard info squiggle (similar to warnings)

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Words that can probably be changed:

• unittests -> unit tests
• coredev -> core dev
• toolcaps -> tool caps?
• crossview -> cross-view

Future considerations:

• style guide entry on American vs British vs "other" English?

[mark-wiemer]

Yep, working on this now using https://streetsidesoftware.com/vscode-spell-checker/, bumped into streetsidesoftware/vscode-cspell-dict-extensions#1081 though :(

[mark-wiemer]

CSpell: Files checked: 89, Issues found: 3343 in 86 files.

Well, at least it's working locally :)

[wsor4035]

ci shouldnt be added till #15 is done

[mark-wiemer]

Fair enough