Improve front matter "added" params

Add missing ones and add the ability to show or hide the badge

Fixes a few more 404 errors in the version picker

site/content/docs/5.3/utilities/link.md

@@ -4,7 +4,8 @@ title: Link
 description: Link utilities are used to stylize your anchors to adjust their color, opacity, underline offset, underline color, and more.
 group: utilities
 toc: true
-added: 5.3
+added:
+  version: "5.3"
 ---
 
 ## Link opacity

site/content/docs/5.3/utilities/object-fit.md

@@ -4,6 +4,8 @@ title: Object fit
 description: Use the object fit utilities to modify how the content of a [replaced element](https://developer.mozilla.org/en-US/docs/Web/CSS/Replaced_element), such as an `<img>` or `<video>`, should be resized to fit its container.
 group: utilities
 toc: true
+added:
+  version: "5.3"
 ---
 
 ## How it works

site/content/docs/5.3/utilities/opacity.md

@@ -3,7 +3,8 @@ layout: docs
 title: Opacity
 description: Control the opacity of elements.
 group: utilities
-added: "5.1"
+added:
+  version: "5.1"
 ---
 
 The `opacity` property sets the opacity level for an element. The opacity level describes the transparency level, where `1` is not transparent at all, `.5` is 50% visible, and `0` is completely transparent.

site/content/docs/5.3/utilities/z-index.md

@@ -4,7 +4,8 @@ title: Z-index
 description: Use our low-level `z-index` utilities to quickly change the stack level of an element or component.
 group: utilities
 toc: true
-added: "5.3"
+added:
+  version: "5.3"
 ---
 
 ## Example