chore: cleanup repo lint + typechecking

[bradzacher]

I noticed a lot of missing coverage with our linting and typechecking setup.

• The top-level test and tools directories weren't being linted/typechecked
• .js files weren't being linted or formatted around the place
• Some of our .d.ts files weren't being linted or formatted

In some cases files were just part of ignore files when they shouldn't've been.
In other cases they weren't properly covered by the nx command config.

This PR fixes all of that with a small reorganisation of the codebase and addition of some config files. It also upgrades prettier.

[typescript-eslint]

Thanks for the PR, @bradzacher!

typescript-eslint is a 100% community driven project, and we are incredibly grateful that you are contributing to that community.

The core maintainers work on this in their personal time, so please understand that it may not be possible for them to review your work immediately.

Thanks again!

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[nx-cloud]

☁️ Nx Cloud Report

CI is running/has finished running commands for commit 1c3604c. As they complete they will appear below. Click to see the status, the terminal output, and the build insights.

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✅ Successfully ran 48 targets

• Node 18 - nx test eslint-plugin
• Node 14 - nx test eslint-plugin --coverage=false
• Node 14 - nx test typescript-estree --coverage=false
• Node 14 - nx test ast-spec --coverage=false
• Node 14 - nx test utils --coverage=false
• Node 14 - nx run-many --target=build --parallel --exclude website
• Node 14 - nx run-many --target=build --parallel --exclude website
• Node 18 - nx test typescript-estree
• Node 14 - nx run-many --target=build --parallel --exclude website
• Node 14 - nx test parser --coverage=false
• Node 14 - nx test scope-manager --coverage=false
• Node 14 - nx test eslint-plugin-internal --coverage=false
• Node 14 - nx test eslint-plugin-tslint --coverage=false
• Node 14 - nx test type-utils --coverage=false
• Node 14 - nx run-many --target=build --parallel --exclude website
• Node 14 - nx run-many --target=build --parallel --exclude website
• Node 14 - nx run-many --target=build --parallel --exclude website
• Node 14 - nx run-many --target=build --parallel --exclude website
• Node 14 - nx test visitor-keys --coverage=false
• Node 14 - nx run-many --target=build --parallel --exclude website
• Node 14 - nx run-many --target=build --parallel --exclude website
• Node 14 - nx run-many --target=build --parallel --exclude website
• Node 18 - nx test visitor-keys
• Node 18 - nx test utils
• Node 18 - nx run-many --target=build --parallel --exclude website
• Node 18 - nx run-many --target=build --parallel --exclude website
• nx run-many --target=typecheck --parallel
• Node 18 - nx test type-utils
• Node 18 - nx run-many --target=build --parallel --exclude website
• Node 18 - nx run-many --target=build --parallel --exclude website
• Node 18 - nx test scope-manager
• Node 18 - nx test eslint-plugin-tslint
• Node 18 - nx run-many --target=build --parallel --exclude website
• Node 18 - nx test parser
• Node 18 - nx run-many --target=build --parallel --exclude website
• nx run-many --target=lint --parallel
• nx run integration-tests:test
• nx run-many --target=build --parallel --exclude website
• nx run-many --target=build --parallel --exclude website
• Node 18 - nx run-many --target=build --parallel --exclude website
• Node 18 - nx test ast-spec
• nx run-many --target=build --parallel --exclude website
• Node 18 - nx run-many --target=build --parallel --exclude website
• nx run-many --target=build --parallel --exclude website
• Node 18 - nx test eslint-plugin-internal
• Node 18 - nx run-many --target=build --parallel --exclude website
• Node 18 - nx run-many --target=build --parallel --exclude website
• nx run-many --target=build --parallel --exclude website

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Sent with 💌 from NxCloud.

[JoshuaKGoldberg]

Lots of changes here that look good - but the tests are borked?

[codecov]

Codecov Report

Merging #6473 (1c3604c) into v6 (cd26357) will increase coverage by 0.00%.
The diff coverage is n/a.

Additional details and impacted files

@@           Coverage Diff           @@
##               v6    #6473   +/-   ##
=======================================
  Coverage   87.12%   87.12%           
=======================================
  Files         362      362           
  Lines       12473    12474    +1     
  Branches     3688     3688           
=======================================
+ Hits        10867    10868    +1     
  Misses       1260     1260           
  Partials      346      346           

Flag	Coverage Δ
unittest	87.12% <ø> (+<0.01%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
...plugin/src/rules/no-redundant-type-constituents.ts	93.79% <ø> (ø)
...lugin/src/rules/padding-line-between-statements.ts	93.83% <ø> (ø)
packages/visitor-keys/src/visitor-keys.ts	100.00% <ø> (ø)
packages/type-utils/src/getContextualType.ts	0.00% <0.00%> (ø)
...ckages/eslint-plugin/src/rules/no-unsafe-return.ts	100.00% <0.00%> (ø)

[JoshuaKGoldberg]

👍 +1, was going to ask for something like this

[JoshuaKGoldberg]

🔥