UI: Spinner statt LADEN-Text, Pills unter Header in Einstellungen

- ViewFallback: dezenter, zentrierter Spinner statt kaum lesbarem
  "LADEN…"-Text zwischen lazy-loaded Views
- Einstellungen: Pill-Navigation jetzt konsistent unter dem Header
  (zuvor lagen die Pills bei allen Tabs ausser "Mein Profil" darüber)

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

src/App.jsx

@@ -28,7 +28,20 @@ const Documents      = lazy(() => import("./views/Documents.jsx"));
 const PrintView      = lazy(() => import("./print/PrintComponents.jsx").then(m => ({ default: m.PrintView })));
 
 function ViewFallback() {
-  return <div style={{ padding: 40, color: "var(--text4)", fontSize: 12, letterSpacing: "0.08em" }}>LADEN…</div>;
+  return (
+    <div style={{ display: "flex", justifyContent: "center", alignItems: "center", minHeight: "calc(100vh - 60px)" }}>
+      <style>{`
+        @keyframes vf-spin { to { transform: rotate(360deg); } }
+        .vf-spinner {
+          width: 40px; height: 40px; border-radius: 50%;
+          border: 2px solid rgba(0,0,0,0.08);
+          border-top-color: rgba(0,0,0,0.45);
+          animation: vf-spin 0.9s linear infinite;
+        }
+      `}</style>
+      <div className="vf-spinner" />
+    </div>
+  );
 }
 
 export default function App() {