DX-1128: localise Code + CodeSnippet (completes the visual lift)

[jamiehenson]

Part of DX-1128. Final PR — localises Code + CodeSnippet (the last @ably/ui visual surface), then applies the end-state cleanup.

What

• Vendored Code, CodeSnippet (+ ApiKeySelector, CopyButton, LanguageSelector, PlainCodeView, TooltipButton, languages) and the transitive Tooltip into src/components/ui/. MDXWrapper rewired; the SessionData seam stays (apiKeys passed as a prop). The subcomponents' internal Heroicon usages are imported directly from @heroicons/react (with the right outline/solid/micro variants), and PlainCodeView's icon prop takes a ReactNode.
• Cleanup now that everything is local: drops the node_modules/@ably/ui Tailwind content glob, deletes the 5 dead vendored CSS files (legacy-buttons, dropdowns, layout, Slider, Flash), prunes shadows → the 2 used tokens and forms → the checkbox block. Compiled global.css 8.4k → 6.7k lines.

After this PR

docs' entire visual surface is local. Remaining @ably/ui imports = insights (×6) + scripts (×2 — the SessionDataProvider/useSessionData context API); the old SessionData Redux store + Flash reducer are gone after rebasing onto the 18.3.1 main (Ken's #3418 migration) — parked infra, not design-system.

Stack (DX-1128)

	PR	Role
	#3409	Design foundation — vendor @ably/ui tokens + reset/core CSS (merged)
	#3410	Local cn + heights utils
	#3411	Docs-native Icon component (Ably glyphs only; Heroicons imported directly)
	#3412	Presentational components (Badge, Button, LinkButton, FeaturedLink, Status)
	#3413	Interactive components (SegmentedControl, TabMenu)
	#3414	ProductTile + product data (leaf)
	#3415	syntax-highlighter util + registry
▶	#3416	Code + CodeSnippet — completes the lift; prunes dead CSS + drops @ably/ui Tailwind scan

#3410–#3416 are a linear stack, each building on the previous; #3409 has merged to main. ▶ = this PR.

Testing

• Load the review app.
• Check a sufficient sample of pages load with no visual regressions.

🤖 Generated with Claude Code

[coderabbitai]

Important

Review skipped

Auto reviews are disabled on this repository. Please check the settings in the CodeRabbit UI or the .coderabbit.yaml file in this repository. To trigger a single review, invoke the @coderabbitai review command.

⚙️ Run configuration

Configuration used: Repository UI

Review profile: CHILL

Plan: Pro

Run ID: 86b5990a-eef2-4165-a472-152383bc3536

You can disable this status message by setting the reviews.review_status to false in the CodeRabbit configuration file.

Use the checkbox below for a quick retry:

• 🔍 Trigger review

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch dx-1128/docs-codesnippet

---

Thanks for using CodeRabbit! It's free for OSS, and your support helps us grow. If you like it, consider giving us a shout-out.

❤️ Share

• X
• Mastodon
• Reddit
• LinkedIn

_{Comment @coderabbitai help to get the list of available commands.}