Login: Sitzungsdauer wählbar (1 Stunde bis 1 Jahr)

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01TiXsPUqw7oeomZ8wZrQW5q

frontend/src/components/AuthBox.tsx

@@ -53,7 +53,15 @@ export function AuthBox() {
         <h2>Login</h2>{" "}
         <input name="user" placeholder="Nutzername" autoComplete="username" />{" "}
         <input name="pass" type="password" placeholder="Passwort" autoComplete="current-password" />{" "}
-        <input name="timeout" type="hidden" value="86400" />{" "}
+        <label>
+          Angemeldet bleiben für{" "}
+          <select name="timeout" defaultValue="86400">
+            <option value="3600">1 Stunde</option>
+            <option value="86400">1 Tag</option>
+            <option value="604800">1 Woche</option>
+            <option value="31536000">1 Jahr</option>
+          </select>
+        </label>{" "}
         <button type="submit" disabled={busy}>Einloggen</button>{" "}
         <p className="muted">Noch kein Konto? <a href="#" onClick={show("register")}>Registrieren</a></p>
       </form>