docs: say what the repository holds in the README

README.md

@@ -1,3 +1,28 @@
-# Org Metadata
+# .github
 
-Global configurations and assets for the cpp-linter organization on GitHub.
+Organization-wide files for [cpp-linter](https://github.com/cpp-linter): the
+[profile README](https://github.com/cpp-linter/.github/blob/main/profile/README.md), the default
+contributing guide, code of conduct, security policy, support page, issue and pull request templates,
+reusable workflows and the brand assets.
+
+[Website](https://cpp-linter.github.io/) ·
+[Get started](https://cpp-linter.github.io/getting-started/) ·
+[Discussions](https://github.com/orgs/cpp-linter/discussions)
+
+## Reusable workflows
+
+The other cpp-linter repositories call the workflows in
+[`.github/workflows/`](https://github.com/cpp-linter/.github/tree/main/.github/workflows) with
+`uses: cpp-linter/.github/.github/workflows/<file>.yml@main`, so a change to one of them reaches
+every repository that calls it on its next run. `main.yml` only runs this repository's own checks.
+
+## Brand assets
+
+[`branding/`](https://github.com/cpp-linter/.github/tree/main/branding) holds the logos, the social
+preview images and the profile banner generator; its
+[README](https://github.com/cpp-linter/.github/blob/main/branding/README.md) lists them. The profile
+banners in `assets/` come from `uv run branding/profile-banner/generate.py`.
+
+## License
+
+[MIT](https://github.com/cpp-linter/.github/blob/main/LICENSE)