ui: Standard-Profil kompakt in die User-Bar oben statt eigener Karte

- Mini-Select neben dem User-Namen, speichert sofort bei change
- "Meine Einstellungen"-Karte entfernt
- Selector erscheint nur, wenn ≥2 Profile verfügbar (sonst nichts zu wählen)

lxc-frontend/app/static/index.html

@@ -19,6 +19,11 @@
           <span class="muted">Angemeldet als</span>
           <strong id="user-name"></strong>
           <span id="user-admin-badge" class="badge admin-badge hidden">Admin</span>
+          <span id="header-profile-wrap" class="header-profile-wrap hidden">
+            <span class="muted">·</span>
+            <span class="muted">Profil:</span>
+            <select id="header-profile" class="header-profile" title="Standard-Profil — wird sofort gespeichert"></select>
+          </span>
           <button type="button" id="logout-btn" class="btn-link">Abmelden</button>
         </div>
       </div>
@@ -71,18 +76,6 @@
       <p id="upload-msg" class="msg"></p>
     </section>
 
-    <section class="card" id="settings-card">
-      <h2>Meine Einstellungen</h2>
-      <form id="settings-form" class="settings-form">
-        <label>
-          Standard-Profil
-          <select id="settings-profile"></select>
-        </label>
-        <button type="submit">Speichern</button>
-      </form>
-      <p id="settings-msg" class="msg"></p>
-    </section>
-
     <section class="card">
       <h2>Jobs</h2>
       <table id="jobs-table">