Add icons subpath export for individual icon imports

[AKnassa]

What this does

Adds a ./icons/* subpath to the package exports so consumers can import a single icon directly:

import Calendar from "@openai/apps-sdk-ui/icons/Calendar"

instead of pulling in the full components/Icon barrel.

Why

Importing from @openai/apps-sdk-ui/components/Icon resolves the ~745-export barrel, which adds real overhead in tooling like Vite/Vitest even when only a few icons are used (see #46). Each icon is a self-contained, side-effect-free module, so a direct subpath import resolves only what's actually used. Measured in a real installed consumer, a single-icon import took ~8 ms vs ~960 ms for the barrel — roughly 124x faster.

What changed

• package.json — one new exports entry, "./icons/*", mirroring the existing ./hooks/* wildcard shape (types before default). No build changes: tsc already emits one ESM module and one .d.ts per icon under dist/{es,types}/components/Icon/svg/, and the existing files globs already ship them.
• Tests (src/components/Icon/Icon.test.tsx) — exports-map shape and condition order, a pre-existing-exports regression guard, svg-dir purity, a case-collision guard, a "no runtime imports" invariant (keeps each icon module barrel-free), a default-export invariant, a barrel↔disk drift guard, and render smoke tests.
• Docs — a short usage note in Icons.mdx, README.md, and Installation.mdx showing the individual-import form (plus the one naming exception: the Object icon is imported as icons/ObjectIcon).
• @types/node added to devDependencies — the new test reads the manifest and icon directory via node:fs/node:path/node:url; it was previously only a transitive dependency.

Notes for reviewers

• This follows the exact proposal in Expose icon subpath exports to avoid loading the full Icon barrel in Vite/Vitest #46. Because it's a wildcard, it also makes importable the ~10 brand icons that exist under svg/ but aren't in the Icon barrel (Instagram, Youtube, etc.). They already ship in dist; if you'd rather keep them out of the public surface, I'm happy to exclude them as a follow-up — just say the word.
• Two touched files live outside src/ (contrary to the AGENTS.md guideline): package.json, because subpath exports can only be declared there, and README.md, to keep it in sync with its src/Installation.mdx twin.
• Verified end-to-end from a packed tarball: single-icon import renders, the barrel import still works (backward compatible), missing names reject cleanly, and types resolve under bundler and node16/nodenext. npm run format / lint / types / test all pass.

Closes #46

[ellismarkf]

@AKnassa how were you able to open this PR? I was blocked by permissions checks from pushing my branch up to origin. 😞

[AKnassa]

Hey @ellismarkf 👋 Yeah, direct pushes to openai/apps-sdk-ui are blocked for non-collaborators — that's the permissions wall you hit. The trick is to go through a fork instead, which doesn't need any write access to this repo:

1. Fork the repo to your own account (the "Fork" button up top, or gh repo fork openai/apps-sdk-ui).
2. Push your branch to your fork rather than to origin — e.g. git push -u <your-fork-remote> <your-branch>.
3. Open the PR from your fork into openai:main (gh pr create --repo openai/apps-sdk-ui --head <your-username>:<your-branch>, or just click "Compare & pull request" on your fork).

That cross-repo flow is the standard way to contribute here, so you never touch origin directly. Happy to help if you hit any snags!

[ellismarkf]

@moustafa-openai @tylersmith-openai

Tagging some OpenAI contributors.

Are there any plans to review and merge open PRs?