chore: add config to generate markdown API docs (#389)

This adds a minimal [docusaurus](https://docusaurus.io) config file that
allows us to use
[docusaurus-plugin-typedoc](https://github.com/tgreyuk/typedoc-plugin-markdown/tree/master/packages/docusaurus-plugin-typedoc)
to generate markdown files that are compatible with docusaurus.

**Context**

As part of web3-storage/web3.storage#2190, I
want to render the typedoc outputs for all our "user facing" packages.
The idea is that I would make a shallow clone of this repo when building
the docs site and run `pnpm run docs:markdown` to generate the markdown
files, then copy them into the content dir, along with the outputs of
`w3up-client` and whatever other packages we end up putting in there.

The plugin really wants to be part of a docusaurus project, but it will
run with just the `@docusaurus/core` dependency and a minimal config
file. `@docusaurus/core` has a peer dependency on `react` and
`react-dom`, so I added some [pnpm
config](https://pnpm.io/package_json#pnpmpeerdependencyrules) to ignore
missing react peer deps.


Here's a quick screenshot of my WIP docs build, as a teaser of things to
come:


![image](https://user-images.githubusercontent.com/678715/214158679-2442f419-1ab7-45df-a2ce-188a4c0de40a.png)

docusaurus.config.js

@@ -0,0 +1,35 @@
+// Minimal [Docusaurus](https://docusaurus.io) configuration to allow us
+// to generate docusaurus-compatible markdown from typedoc output.
+
+const config = {
+  title: 'Web3.Storage Documentation',
+  tagline: 'The simple file storage service for IPFS and Filecoin',
+  url: 'https://docs.web3.storage',
+  baseUrl: '/',
+  onBrokenLinks: 'warn',
+  onBrokenMarkdownLinks: 'warn',
+  favicon: 'img/favicon.ico',
+
+  // Even if you don't use internalization, you can use this field to set useful
+  // metadata like html lang. For example, if your site is Chinese, you may want
+  // to replace "en" with "zh-Hans".
+  i18n: {
+    defaultLocale: 'en',
+    locales: ['en'],
+  },
+
+  plugins: [
+    [
+      'docusaurus-plugin-typedoc',
+      {
+        tsconfig: './tsconfig.json',
+        out: 'markdown',
+        sidebar: {
+          categoryLabel: 'w3protocol',
+        },
+      },
+    ],
+  ],
+}
+
+module.exports = config

package.json

@@ -13,12 +13,16 @@
     "test": "pnpm -r --if-present run test",
     "check": "pnpm -r --if-present run check",
     "build": "pnpm -r --if-present run build",
-    "docs": "pnpm run build && typedoc --out docs"
+    "docs": "pnpm run build && typedoc --out docs",
+    "docs:markdown": "pnpm run build && docusaurus generate-typedoc"
   },
   "devDependencies": {
+    "@docusaurus/core": "^2.2.0",
+    "docusaurus-plugin-typedoc": "^0.18.0",
     "lint-staged": "^13.1.0",
     "prettier": "2.8.3",
     "simple-git-hooks": "^2.8.1",
+    "typedoc-plugin-markdown": "^3.14.0",
     "typescript": "4.9.4",
     "wrangler": "^2.8.0"
   },
@@ -43,5 +47,12 @@
     "typedoc": "^0.23.22",
     "typedoc-plugin-missing-exports": "^1.0.0"
   },
-  "packageManager": "[email protected]"
+  "packageManager": "[email protected]",
+  "pnpm": {
+    "peerDependencyRules": {
+      "ignoreMissing": [
+        "react*"
+      ]
+    }
+  }
 }