Increase visibility of active menu option in docs page (#3339)

Fixes #608

<img width="421" height="112" alt="image"
src="https://github.com/user-attachments/assets/dcd89593-002d-43c6-9db6-e43fa4d4b497"
/>

Author: AndreasArvidsson

packages/app-web-docs/src/css/custom.scss

@@ -25,3 +25,9 @@
 .pointer {
   cursor: pointer;
 }
+
+// Make active menu option more visible in Docusaurus
+/* stylelint-disable-next-line selector-class-pattern */
+.navbar__item.navbar__link--active {
+  box-shadow: inset 0 -3px 0 currentcolor;
+}

packages/app-web-docs/src/docs/contributing/adding-a-new-scope.md

@@ -14,6 +14,7 @@ Some scope types are used internally by Cursorless, so they are not included in
 access, private.fieldAccess
 text fragment, textFragment
 disqualify, disqualifyDelimiter
+pair delimiter, pairDelimiter
 core, interior
 ```