Stop stretching the settings nav to match content height

Confirmed via real getBoundingClientRect measurements from the user's
own browser that the previous fix's text alignment was already exact
(navItem/heading/saveBtn all centerY=88, pixel-perfect) — so that
wasn't the remaining problem. The actual issue was navCard itself:
1764px tall, because it was stretched (h-100 + row align-items-stretch)
to match the Notifications page's own long column of cards, leaving
~1500px of empty space below the last nav item ("Backup").

Dropped the stretch. The nav card now sits at its own natural, compact
height — still top-aligned with the content column (that part was
never broken) and still using the tightened list-group-item padding
so its text lines up with the content heading, just without forcing
its box to match a content column that can be arbitrarily tall.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

web/src/pages/Settings.tsx

@@ -14,9 +14,9 @@ export default function Settings() {
   return (
     <>
       <h2 className="page-title mb-3">Settings</h2>
-      <div className="row align-items-stretch">
+      <div className="row">
         <div className="col-12 col-md-3 col-lg-2 mb-3 mb-md-0">
-          <div className="card h-100">
+          <div className="card">
             {/* Tabler's default list-group-item padding (1.25rem) is sized for
                 standalone list cards, not a nav sidebar — at that padding the
                 first item's text sits ~12px below where the content column's