Refactor core modules + revamp all demo pages

[ianmcburnie]

Refactor core modules + revamp all demo pages

Summary

• Modernize 12 core modules to current JS patterns: replace var/keyCode/Object.assign, use ES module named imports/exports, arrow functions, spread, optional chaining, and nullish coalescing. Modules updated: makeup-exit-emitter, makeup-focusables, makeup-key-emitter,
  makeup-expander, makeup-keyboard-trap, makeup-screenreader-trap, makeup-modal, makeup-navigation-emitter, makeup-roving-tabindex, makeup-active-descendant, makeup-typeahead, makeup-next-id, makeup-prevent-scroll-keys
• Increase unit test coverage across all refactored modules, adding tests for previously uncovered branches, edge cases, and custom events
• Revamp all demo pages (core and UI) with a consistent structure: flat layout, breadcrumb navigation, on-page event logging instead of console output,

  ---

  -separated sections, and suppressed favicon requests
• Fix broken UI demo layout caused by docs.css updates — removed legacy
  + wrapper pattern across all 17 UI demo pages, removed boilerplate eBay Skin attribution paragraphs
• Update ESLint config to ES2022

Test plan

• Run npm run test:unit — all unit tests pass
• Run npm run test:e2e — all Playwright tests pass
• Load each revamped demo page and verify layout renders correctly with docs.css
• Verify on-page event logs fire correctly for interactive demos

🤖 Generated with https://claude.com/claude-code

[ianmcburnie]

@saiponnada Adding you for visibility, I do not expect you to review all these files, but as a high level want to make sure you are aware of and approve this refactor.

[saiponnada]

Looks good to me — I’m aligned with the intent here. I’ve skimmed through at a high level. Appreciate you looping me in.

[LuLaValva]

Looks like Claude did a great job here! I didn't read through the docs changes, but nothing big stuck out to me on the JS side. Just a few comments about the TODO comments that were added, but regardless I think this is good to merge