feat: Add various content types to docusaurus (#7231)

This brings blog posts, showcase posts, and newsletter editions into the Docusaurus site.

It also adds support for using TailwindCSS inside a container. So this will probably end up being the new freesewing.org site in v4.

sites/dev/docs/tutorials/pattern-design/part2/creating-the-closure/readme.mdx

@@ -1,6 +1,6 @@
 ---
 title: Creating the closure
-order: 91
+sidebar_position: 91
 ---
 
 Things are starting to look good, but we can't fit the bib over the baby's head like this.
@@ -60,28 +60,27 @@ function draftBib({
   tweak _ measurements.head / 12
   )
 
+  points.rightCp1 = points.right.shift(
+  90,
+  points.bottom.dy(points.right) / 2
+  )
+  points.bottomCp2 = points.bottom.shift(
+  0,
+  points.bottom.dx(points.right) / 2
+  )
 
-    points.rightCp1 = points.right.shift(
-      90,
-      points.bottom.dy(points.right) / 2
-    )
-    points.bottomCp2 = points.bottom.shift(
-      0,
-      points.bottom.dx(points.right) / 2
-    )
+  paths.quarterNeck = new Path()
+  .move(points.right)
+  .curve(
+  points.rightCp1,
+  points.bottomCp2,
+  points.bottom
+  )
+  .hide()
 
-    paths.quarterNeck = new Path()
-      .move(points.right)
-      .curve(
-        points.rightCp1,
-        points.bottomCp2,
-        points.bottom
-      )
-      .hide()
-
-    delta = paths.quarterNeck.length() - target
-    if (delta > 0) tweak = tweak * 0.99
-    else tweak = tweak * 1.02
+  delta = paths.quarterNeck.length() - target
+  if (delta > 0) tweak = tweak _ 0.99
+  else tweak = tweak _ 1.02
 
 } while (Math.abs(delta) > 1)