CODE_LANGS: only add React (and similar) when docs actually fence them

[drQedwards]

Status

Follow-up from #2780 and @ElliotFriend’s review: CODE_LANGS in config/constants.ts is the subset of languages used as CodeExample tab labels, not every language Prism can highlight.

Done in #2780 (README + config/constants.ts stay in lockstep):

Key	Tab label	Why
css	CSS	Already fenced in docs/build/apps/example-application-tutorial/overview.mdx
html	HTML	Already fenced across the example-application tutorial and guestbook frontend
jsx	JSX	Already fenced in docs/build/guides/dapps/react.mdx and docs/tools/openzeppelin-relayer.mdx

Not added (no fences in the docs today): react, html5, css3.

Future: when react (or html5/css3) should land

Add a CODE_LANGS key only when a CodeExample fence actually uses that language id, so the tab does not fall back to “Example”. Until then, React content in the docs should keep using jsx / tsx (what the files already use).

See the comment below for where React already lives in the ecosystem and where a react language id could show up later.

[drQedwards]

@ElliotFriend thanks again — you’re right that we should not list react / html5 / css3 until a CodeExample actually specifies those languages.

#2780 now only adds keys the docs already fence (css, html as HTML, jsx). This issue is the place to track a future react key.

Where React already shows up (using jsx / tsx, not react)

The Stellar frontend path is React today; the fences just don’t use the language id react:

• docs/build/guides/dapps/react.mdx — “Create a frontend for your dapp using React” (@soroban-react, Freighter). Still draft: true. Fences are already jsx / tsx (imports, MintButton, hooks).
• docs/build/guides/freighter/integrate-freighter-react.mdx — Freighter in a React dapp; live, fences are tsx (WalletData).
• docs/tools/openzeppelin-relayer.mdx — client page is fenced as jsx title="page.tsx" ("use client", React.useState).
• Example app / guestbook frontends — lots of html + js in the tutorial (overview.mdx also has the css fence). Those are the closest “web UI” tabs we have outside the React guides.
• Upstream samples — stellar/soroban-example-dapp is the React crowdfund the guides cite; @soroban-react is the community React stack.

Prism (and our CodeExample lookup) treats jsx / tsx as the language, with the tab label coming from CODE_LANGS. That’s why jsx is in the map now and react is not: no fence in the repo is written as ```react.

Where we could see react as a language later

A react: 'React' entry would earn its place if we:

1. Publish the draft React dapp guide (react.mdx) and, in a CodeExample, use ```react when we want a tab literally labeled “React” next to e.g. Svelte/vanilla JS (guestbook is SvelteKit + Tailwind today).
2. Add a multi-language frontend CodeExample (React vs. the existing JS/HTML tutorial vs. a future wallet UI) so the tab set needs a React label distinct from JSX/TSX.
3. Document @stellar/typescript-wallet-sdk / Freighter + React side by side with the Kotlin/TS/Dart/Swift wallet tabs (WalletCodeExample already keys off CODE_LANGS).

Until one of those fences exists, adding react would document a language we don’t use, which is exactly the concern you raised. Happy to add it in a follow-up PR the moment a ```react block lands.

[ElliotFriend]

this one closed when i merged #2780. if you find a published react code example, feel free to create a new issue or re-open this one. thanks!