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]>

packages/content-loader/src/sidebar.ts

@@ -1,7 +1,7 @@
 /**
  * Builds one sidebar per (product, version, language) out of the loaded pages,
  * deriving it from `_category_.json` and from the
- * handwritten sidebar files of the runner docs.
+ * handwritten sidebar files of the runner and the cli docs.
  */
 
 import { defaultLocale } from './products';
@@ -44,7 +44,7 @@ export interface SidebarGroup {
 
 export type SidebarEntry = SidebarLink | SidebarGroup;
 
-/** A hand written sidebar file, as used by the runner docs. */
+/** A hand written sidebar file, as used by the runner and the cli docs. */
 export type SidebarSourceItem =
   | string
   | { type: 'doc'; id: string; label?: string }
@@ -148,7 +148,7 @@ function treeOf(pages: SidebarPage[]): Tree {
   return { build, label };
 }
 
-/** Sidebar described by a hand written sidebar file, used by the runner docs. */
+/** Sidebar described by a hand written sidebar file, used by the runner and the cli docs. */
 function fromSidebarSource(
   items: SidebarSourceItem[],
   pages: SidebarPage[],