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/path/setclass/readme.mdx

@@ -0,0 +1,42 @@
+---
+title: Path.setClass()
+---
+
+The `Path.setClass()` method sets the CSS class(es) of the path.
+
+## Signature
+
+```js
+Path path.setClass(string className)
+```
+
+:::tipThis method is chainable as it returns the `Path` object:::
+
+## Example
+
+<Example caption="Example of the Path.setClass() method">
+```js
+({ Point, points, Path, paths, part }) => {
+
+  points.from = new Point(5, 10)
+  points.to = new Point(95, 10)
+
+  paths.line = new Path()
+    .move(points.from)
+    .line(points.to)
+    .setClass('note dashed')
+
+  return part
+}
+```
+</Example>
+
+## Notes
+
+The main purpose of this method is to save your some typing,
+as the two following calls yield the same result:
+
+```js
+path.attr('class', 'fabric', true)
+path.setClass('fabric')
+```