fix: replace invalid <p> wrapping Button with <div> (#768)

* fix: replace invalid <p> wrapping Button with <div>

The Button component renders a <div> in its primary variant. HTML
disallows block elements inside <p>, so browsers auto-close the <p>
during parsing and React 19 reports a hydration mismatch. The
float="center" attribute was non-functional, so rendering is unchanged.

* chore: gitignore .playwright-mcp run artifacts

src/pages/manage/activity/index.mdx

@@ -129,9 +129,9 @@ NetBird can stream audit events to your Security Information and Event Managemen
 
 ## Get Started
 
-<p float="center" >
+<div>
     <Button name="button" className="button-5" onClick={() => window.open("https://netbird.io/pricing")}>Use NetBird</Button>
-</p>
+</div>
 
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