fix: make buttons always visible in AdminUserRestrictionsPage

Bottom bar changes:
- Always visible when user selected (not hidden)
- Buttons disabled when no changes (clearer state)
- Moved outside inner block to prevent hiding

Action column changes:
- "↺ Zurück" button always visible per feature
- Disabled when no override exists (grayed out)
- Consistent button presence improves UX

This fixes the issue where buttons were not shown
because they were conditionally rendered.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

frontend/src/pages/AdminUserRestrictionsPage.jsx

@@ -434,15 +434,19 @@ export default function AdminUserRestrictionsPage() {
 
                           {/* Action */}
                           <td style={{ padding: '12px 16px', textAlign: 'right' }}>
-                            {override && (
                             <button
                               className="btn btn-secondary"
                               onClick={() => handleChange(feature.id, '')}
-                                style={{ padding: '4px 8px', fontSize: 11 }}
+                              disabled={!override}
+                              style={{
+                                padding: '4px 8px',
+                                fontSize: 11,
+                                opacity: override ? 1 : 0.4,
+                                cursor: override ? 'pointer' : 'not-allowed'
+                              }}
                             >
-                                ↺ Zurück zu Standard
+                              ↺ Zurück
                             </button>
-                            )}
                           </td>
                         </tr>
                       )
@@ -453,7 +457,25 @@ export default function AdminUserRestrictionsPage() {
             </table>
           </div>
 
-          {/* Fixed Bottom Bar */}
+
+          {/* Legend */}
+          <div style={{
+            marginTop: 16, padding: 12, background: 'var(--surface2)',
+            borderRadius: 8, fontSize: 12, color: 'var(--text3)', marginBottom: 100
+          }}>
+            <strong>Eingabe:</strong>
+            <div style={{ marginTop: 8, display: 'flex', gap: 24, flexWrap: 'wrap' }}>
+              <span><strong>Leer</strong> = Tier-Standard nutzen (kein Override)</span>
+              <span><strong style={{ color: 'var(--danger)' }}>0</strong> = Feature deaktiviert</span>
+              <span><strong>∞ oder leer</strong> = Unbegrenzt (bei Count-Features)</span>
+              <span><strong>1-999999</strong> = Limit-Wert</span>
+            </div>
+          </div>
+        </>
+      )}
+
+      {/* Fixed Bottom Bar - Always visible when user selected */}
+      {selectedUser && (
         <div style={{
           position: 'fixed', bottom: 0, left: 0, right: 0,
           background: 'var(--bg)', borderTop: '1px solid var(--border)',
@@ -477,21 +499,6 @@ export default function AdminUserRestrictionsPage() {
             {saving ? 'Speichern...' : hasChanges ? `${Object.keys(changes).length} Änderung(en) speichern` : 'Keine Änderungen'}
           </button>
         </div>
-
-          {/* Legend */}
-          <div style={{
-            marginTop: 16, padding: 12, background: 'var(--surface2)',
-            borderRadius: 8, fontSize: 12, color: 'var(--text3)', marginBottom: 100
-          }}>
-            <strong>Eingabe:</strong>
-            <div style={{ marginTop: 8, display: 'flex', gap: 24, flexWrap: 'wrap' }}>
-              <span><strong>Leer</strong> = Tier-Standard nutzen (kein Override)</span>
-              <span><strong style={{ color: 'var(--danger)' }}>0</strong> = Feature deaktiviert</span>
-              <span><strong>∞ oder leer</strong> = Unbegrenzt (bei Count-Features)</span>
-              <span><strong>1-999999</strong> = Limit-Wert</span>
-            </div>
-          </div>
-        </>
       )}
     </div>
   )