Add mock options in frontend and removed from environment variables

src/static/admin.html

@@ -188,6 +188,16 @@
             <button type="submit" class="btn btn-primary">Save</button>
           </form>
         </div>
+        <h3 style="margin:1.5rem 0 1rem">Mock Mode</h3>
+        <div class="card" style="max-width:440px">
+          <p style="color:var(--text-muted);font-size:.9rem;margin-bottom:1rem">
+            When enabled, gate open requests always succeed without contacting AVConnect.
+          </p>
+          <label style="display:flex;align-items:center;gap:.75rem;cursor:pointer;margin:0">
+            <input type="checkbox" id="mock-toggle" style="width:1.1rem;height:1.1rem;flex-shrink:0;cursor:pointer" />
+            <span style="font-weight:600">Enable mock AVConnect</span>
+          </label>
+        </div>
       </div>
 
       <!-- ── Statistics pane ───────────────────────────────────────────── -->