feat: add @penrose/panels to the monorepo

[wodeni]

Description

Related issue/PR: #659, #671

This PR migrates the IDE into our monorepo.

Implementation strategy and design decisions

• Update the usage of stepUntilConvergence to account for the API change on error handling
• Drop CRA and switch to ESBuild

Checklist

• I have commented my code, particularly in hard-to-understand areas
• My changes generate no new warnings
• New and existing tests pass locally using yarn test
• I ran yarn docs and there were no errors when generating the HTML site
• My code follows the style guidelines of this project (e.g.: no ESLint warnings)

Open questions

• CRA doesn't seem to work well with ESBuild outputs. For instance, if I run yarn start in panels, CRA complains about Module parse failed: Unexpected token (749:18). Haven't investigated this further, but I'm assuming this is the same issue as I saw in feat: React component library #671, i.e. ES6 operators not supported by CRA (?).

[codecov]

Codecov Report

Merging #681 (e37b9fc) into main (d65ac8d) will not change coverage.
The diff coverage is n/a.

❗ Current head e37b9fc differs from pull request most recent head e97af8b. Consider uploading reports for the commit e97af8b to get more accurate results

@@           Coverage Diff           @@
##             main     #681   +/-   ##
=======================================
  Coverage   66.81%   66.81%           
=======================================
  Files          44       44           
  Lines        7105     7105           
  Branches     1335     1335           
=======================================
  Hits         4747     4747           
  Misses       2349     2349           
  Partials        9        9           

Impacted Files	Coverage Δ
packages/core/src/index.ts	77.51% <ø> (ø)

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