Add documentation for gt, the Gitea CLI (#603)

Adds a CLI product for gt (https://gitea.com/gitea/cli), set up like the runner, with short guides for installation, logging in, CI and scripting. Each command's details stay in gt <command> --help. Until the first release, the docs are served at /cli/; make cut-version PRODUCT=cli VERSION=0.1 adds the release series.

Closes https://gitea.com/gitea/cli/issues/16

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Co-authored-by: silverwind <[email protected]>
Reviewed-on: https://gitea.com/gitea/docs/pulls/603
Reviewed-by: Lunny Xiao <[email protected]>
Reviewed-by: silverwind <[email protected]>

README.md

@@ -3,13 +3,14 @@
 The sources of [docs.gitea.com](https://docs.gitea.com), built with
 [Astro](https://astro.build) and [Starlight](https://starlight.astro.build).
 
-The site covers three products, all served from this repository:
+The site covers four products, all served from this repository:
 
 | Product | Content | Versions | Languages |
 | --- | --- | --- | --- |
 | Docs | `docs/`, `versioned_docs/`, `i18n/` | next, 28, 1.27 … 1.22 | English, 简体中文, 繁體中文 |
 | API | `static/swagger-*.json`, `static/openapi3-*.json` | next, 28, 1.27 … 1.22 | English |
 | Runner | `runner-docs/`, `runner-docs_versioned_docs/` | develop, 5 … 0 | English |
+| CLI | `cli-docs/`, `cli-docs_versioned_docs/` | develop | English |
 
 The enterprise documentation is built and deployed from its own repository and
 reached through `/enterprise/`, which a Cloudflare worker maintained elsewhere
@@ -53,6 +54,7 @@ group from the `_category_.json` of its directory.
 ```shell
 make cut-version PRODUCT=docs VERSION=1.28
 make cut-version PRODUCT=runner VERSION=6
+make cut-version PRODUCT=cli VERSION=0.1
 ```
 
 This freezes the current tree, its translations and its sidebar. The label of
@@ -115,6 +117,16 @@ workflow runs weekly and opens a pull request whenever the runner's CLI or
 example configuration changed. Generating them needs Go, since the script builds
 the runner binary.
 
+## CLI docs
+
+The documentation of `gt`, the Gitea CLI from
+[gitea/cli](https://gitea.com/gitea/cli), is laid out like the runner docs, with
+its sidebar in `cli-sidebars.js`. No series is documented yet, so `cli-docs/` is
+served at `/cli/`. Once a release exists, cut its series and list it in
+`cliSeries` in `packages/content-loader/src/products.ts`, which moves the develop
+docs to `/cli/develop/`. The guides leave the flags of each command to
+`gt <command> --help`.
+
 ## Deployment
 
 `main` is built and published by the `Build and Publish Docs site` workflow, to