Fix profile nav unread dots anchoring to the nav column instead of the button

The .profile-nav__unread-dot is absolutely positioned (top:50%, left:-6px),
but the nav buttons weren't a positioning context (.btn/.focus-ring set no
position), so the Admin (and latent Messages) dot resolved against the whole
nav column — showing mid-height at the far left instead of on its button.
Make .profile-modal__nav > button position:relative so each dot anchors to
its own button.

Co-Authored-By: Claude Opus 4.8 <[email protected]>

css/tailwind.source.css

@@ -3544,6 +3544,13 @@
     overflow-x: visible;
   }
 
+  /* Nav buttons host an absolutely-positioned unread dot, so they must be the
+     positioning context — otherwise the dot resolves against the whole nav
+     column (top:50%/left:-6px of the list, not the button). */
+  .profile-modal__nav > button {
+    position: relative;
+  }
+
   .profile-nav__unread-dot {
     position: absolute;
     top: 50%;