feat: restruction of admin sidebar, button slightly adjusted, member tiers header added, routing for sidbar adjusted

src/pages/admin/AdminMemberTiers.js

@@ -150,9 +150,15 @@ const AdminMemberTiers = () => {
     <div className="space-y-6">
       {/* Header and Actions */}
       <div className="flex flex-col sm:flex-row sm:items-center justify-between gap-4">
-        <p className="text-muted-foreground">
-          Configure tier names, time ranges, and badges displayed in the members directory.
-        </p>
+        <div>
+
+          <h1 className="text-4xl md:text-5xl font-semibold text-[var(--purple-ink)] mb-4" style={{ fontFamily: "'Inter', sans-serif" }}>
+            Members Tiers
+          </h1>
+          <p className="text-muted-foreground">
+            Configure tier names, time ranges, and badges displayed in the members directory.
+          </p>
+        </div>
         <div className="flex items-center gap-2">
           {hasChanges && (
             <Button variant="outline" onClick={handleDiscardChanges}>