feat: initialize ObsiGate frontend with SPA structure, search history, and autocomplete functionality

frontend/app.js

@@ -1895,12 +1895,37 @@
     if (recentFilter) recentFilter.value = selectedContextVault === "all" ? "" : selectedContextVault;
     if (dashboardFilter) dashboardFilter.value = selectedContextVault;
 
+    // Mise à jour visuelle des dropdowns personnalisés
+    updateCustomDropdownVisual("vault-filter-dropdown", selectedContextVault);
+    updateCustomDropdownVisual("vault-quick-select-dropdown", selectedContextVault);
+
     // Update vault context indicator
     if (contextText) {
       contextText.textContent = selectedContextVault === "all" ? "All" : selectedContextVault;
     }
   }
 
+  /**
+   * Updates the visual state of a custom dropdown based on its current value.
+   */
+  function updateCustomDropdownVisual(dropdownId, value) {
+    const dropdown = document.getElementById(dropdownId);
+    if (!dropdown) return;
+
+    const selectedText = dropdown.querySelector(".custom-dropdown-selected");
+    const options = dropdown.querySelectorAll(".custom-dropdown-option");
+
+    options.forEach((opt) => {
+      const optValue = opt.getAttribute("data-value");
+      if (optValue === value) {
+        opt.classList.add("selected");
+        if (selectedText) selectedText.textContent = opt.textContent;
+      } else {
+        opt.classList.remove("selected");
+      }
+    });
+  }
+
   function scrollTreeItemIntoView(element, alignToTop) {
     if (!element) return;
     const scrollContainer = document.getElementById("sidebar-panel-vaults");

frontend/index.html

@@ -375,7 +375,7 @@
                 <h2>Derniers fichiers ouverts</h2>
                 <span id="dashboard-count" class="dashboard-badge"></span>
               </div>
-              <div class="dashboard-actions">
+              <div class="dashboard-actions hidden">
                 <select id="dashboard-vault-filter" class="dashboard-filter" aria-label="Filtrer par vault">
                   <option value="all">Tous les vaults</option>
                 </select>