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/point/shift/readme.mdx

@@ -0,0 +1,36 @@
+---
+title: Point.shift()
+---
+
+The `Point.shift()` method returns a new `Point` that is `distance` (mm) away
+in the direction of `angle` (degrees).  An angle of 0° points to the right, and
+the angle increases counterclockwise.
+
+## Signature
+
+```js
+Point point.shift(float angle, float distance)
+```
+
+## Example
+
+<Example caption="An example of the Point.shift() method">
+```js
+({ Point, points, macro, part }) => {
+
+  points.A = new Point(90, 40)
+    .setText("Point A", "right text-sm")
+  points.B = points.A.shift(155, 70)
+    .setText("Point B is point A shifted 7 cm\nat a 155 degree angle", "text-sm")
+    .attr("data-text-lineheight", 6)
+
+  macro("ld", {
+    from: points.B,
+    to: points.A,
+    d: -10
+  })
+
+  return part
+}
+```
+</Example>