chore(docs): Added stackPrefix settings doc

markdown/dev/reference/settings/stackprefix/en.md

@@ -0,0 +1,24 @@
+---
+title: stackPrefix
+---
+
+The `stackPrefix` setting allows you to specify a prefix that will be used
+for all stacks in the pattern. Its default value is `` (no prefix).
+
+## Signature
+
+```js
+const settings = {
+  String stackPrefix=''
+}
+```
+
+## Example
+
+```js
+import { Aaron } from "@freesewing/aaron";
+
+const pattern = new Aaron({
+  stackPrefix: "something-else"
+})
+```