Styles: Less file housecleaning

[jeremywiebe]

A round of Less file cleanup. There were a bunch of unused variables and files. I figured out what was unused by running yarn build --watch and then starting to delete variables. Any time there was a varaible that was still in use, there would be an error like this [!] (plugin commonjs--resolver) Error: variable @gray95 is undefined.

• Get rid of variables.shared.less and move the single used variable to variables.less
• Rename articles.less to styles.less as it has rules for both articles and exercises!
• Remove completely unused variables.bootstrap.less
• Remove outdated comment
• Extract zoom styles to own file out of styles.less
• Trim out more unused variables from variables.less

Issue: --none--

Test plan:

yarn build is successful (our builds process Less files into CSS and so if there's variable references that no longer exist, it will fail)

[github-actions]

Size Change: +1 B (0%)

Total Size: 855 kB

Filename	Size	Change
packages/perseus/dist/es/index.js	414 kB	+1 B (0%)

ℹ️ View Unchanged

Filename	Size
packages/kas/dist/es/index.js	38.3 kB
packages/kmath/dist/es/index.js	4.27 kB
packages/math-input/dist/es/index.js	78.2 kB
packages/math-input/dist/es/strings.js	1.79 kB
packages/perseus-core/dist/es/index.js	1.48 kB
packages/perseus-editor/dist/es/index.js	276 kB
packages/perseus-linter/dist/es/index.js	21.6 kB
packages/perseus/dist/es/strings.js	3.29 kB
packages/pure-markdown/dist/es/index.js	3.67 kB
packages/simple-markdown/dist/es/index.js	12.4 kB

_{compressed-size-action}

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 70.73%. Comparing base (9cb0321) to head (d386a85).

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #877      +/-   ##
==========================================
+ Coverage   70.37%   70.73%   +0.36%     
==========================================
  Files         513      516       +3     
  Lines      106106   106139      +33     
  Branches     7713    11503    +3790     
==========================================
+ Hits        74672    75082     +410     
+ Misses      31317    31057     -260     
+ Partials      117        0     -117     

Files	Coverage Δ
packages/perseus/src/renderer.tsx	93.98% <100.00%> (+1.46%)	⬆️
packages/perseus/src/styles/shared.ts	100.00% <100.00%> (ø)
packages/perseus/src/util/sizing-utils.ts	78.26% <100.00%> (-2.18%)	⬇️

... and 122 files with indirect coverage changes

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[jeremywiebe]

This chunk of styles was moved to zoom.less

[khan-actions-bot]

Gerald

Required Reviewers

• @Khan/perseus for changes to .changeset/grumpy-icons-retire.md, packages/perseus/src/renderer.tsx, packages/perseus/src/styles/perseus-renderer.less, packages/perseus/src/styles/shared.ts, packages/perseus/src/styles/styles.less, packages/perseus/src/styles/variables.less, packages/perseus/src/styles/zoom.less, packages/perseus/src/util/sizing-utils.ts

---

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[nedredmond]

All looks good to me! Thanks, @jeremywiebe !

[github-actions]

npm Snapshot: Published

Good news!! We've packaged up the latest commit from this PR (d386a85) and published it to npm. You
can install it using the tag PR877.

Example:

yarn add @khanacademy/perseus@PR877

If you are working in Khan Academy's webapp, you can run:

./dev/tools/bump_perseus_version.sh -t PR877