feat: implement core backend API with data models, SSE, index management, and initial admin bootstrap.

frontend/app.js

@@ -1940,6 +1940,64 @@
     safeCreateIcons();
   }
 
+  /**
+   * Refreshes the sidebar tree while preserving the expanded state of vaults and folders.
+   */
+  async function refreshSidebarTreePreservingState() {
+    // 1. Capture expanded vaults
+    const expandedVaults = Array.from(document.querySelectorAll(".vault-item")).filter(v => {
+      const children = document.getElementById(`vault-children-${v.dataset.vault}`);
+      return children && !children.classList.contains("collapsed");
+    }).map(v => v.dataset.vault);
+
+    // 2. Capture expanded directories
+    const expandedDirs = Array.from(document.querySelectorAll(".tree-item[data-path]")).filter(item => {
+      const vault = item.dataset.vault;
+      const path = item.dataset.path;
+      const children = document.getElementById(`dir-${vault}-${path}`);
+      return children && !children.classList.contains("collapsed");
+    }).map(item => ({ vault: item.dataset.vault, path: item.dataset.path }));
+
+    // 3. Capture selected path
+    const selectedItem = document.querySelector(".tree-item.path-selected");
+    const selectedState = selectedItem ? { vault: selectedItem.dataset.vault, path: selectedItem.dataset.path } : null;
+
+    // 4. Reload vaults (rebuilds root list)
+    await loadVaults();
+
+    // 5. Re-expand vaults
+    for (const vName of expandedVaults) {
+      const vItem = document.querySelector(`.vault-item[data-vault="${CSS.escape(vName)}"]`);
+      if (vItem) {
+        await toggleVault(vItem, vName, true);
+      }
+    }
+
+    // 6. Re-expand directories (parents first)
+    expandedDirs.sort((a, b) => a.path.split("/").length - b.path.split("/").length);
+    for (const dir of expandedDirs) {
+      const dItem = document.querySelector(`.tree-item[data-vault="${CSS.escape(dir.vault)}"][data-path="${CSS.escape(dir.path)}"]`);
+      const container = document.getElementById(`dir-${dir.vault}-${dir.path}`);
+      if (dItem && container && container.classList.contains("collapsed")) {
+        try {
+          await loadDirectory(dir.vault, dir.path, container);
+          container.classList.remove("collapsed");
+          const chev = dItem.querySelector("[data-lucide]");
+          if (chev) chev.setAttribute("data-lucide", "chevron-down");
+        } catch (e) {
+          console.error(`Failed to re-expand ${dir.vault}/${dir.path}`, e);
+        }
+      }
+    }
+
+    // 7. Restore selection
+    if (selectedState) {
+      await focusPathInSidebar(selectedState.vault, selectedState.path, { alignToTop: false });
+    }
+    
+    safeCreateIcons();
+  }
+
   async function toggleVault(itemEl, vaultName, forceExpand) {
     const childContainer = document.getElementById(`vault-children-${vaultName}`);
     if (!childContainer) return;
@@ -3369,7 +3427,7 @@
       showToast("✓ Paramètres sauvegardés", "success");
       
       // Refresh the UI to apply the filter
-      await Promise.all([loadVaults(), refreshTagsForContext()]);
+      await Promise.all([refreshSidebarTreePreservingState(), refreshTagsForContext()]);
     } catch (err) {
       console.error("Failed to save hidden files settings:", err);
       const errorMsg = err.message || "Erreur inconnue";