chore: Port FreeSewing.dev to docusaurus

The replaces the NextJS site powering FreeSewing.dev with a Docusaurus
setup. It's part of my efforts to simplify FreeSewing's setup so we can
focus on our core value proposition.

sites/dev/docs/reference/api/store/set/readme.mdx

@@ -0,0 +1,45 @@
+---
+title: Store.set()
+---
+
+The `Store.set()` method stores the value of `value` in the store under key
+`key`.
+
+## Signature
+
+```js
+Store store.set(mixed key, mixed value)
+```
+
+:::tipThis method is chainable as it returns the `Store` object:::
+
+## Example
+
+```js
+const store = new Store()
+store.set('example', 'Hi there')
+```
+
+## Notes
+
+You can get/set nested keys either through dot-notation, or by passing an
+array:
+
+```js
+const store = new Store()
+
+store.set('my.nested.example', 'Hi there')
+store.set(['my', 'other', 'nested', 'example'], 'Oh hi again')
+
+let value
+// Dot notation
+value = store.get('my.nested.example') // works
+value = store.get('my.other.nested.example') // works
+// Using an array
+value = store.get(['my', 'nested', 'example']) // works
+value = store.get(['my', 'other', 'nested', 'example']) // works
+// Direct access to the store object
+value = store.my.nested.example // Also works
+value = store.my.other.nested.example // Also works
+```
+