feat: Implement sidebar collapse and expand functionality

- Add CSS for collapsed sidebar state and transitions
- Introduce SidebarToggle class for managing collapse/expand logic
- Integrate SidebarToggle initialization in main script
- Add toggle button to navbar and make mini sidebar clickable
- Store sidebar collapsed state in localStorage
- Filter image files and directories in view mode via FileTree
- Make navbar brand clickable to navigate to collection root or home

static/js/app.js

@@ -277,6 +277,9 @@ document.addEventListener('DOMContentLoaded', async () => {
         darkMode.toggle();
     });
 
+    // Initialize sidebar toggle
+    const sidebarToggle = new SidebarToggle('sidebarPane', 'sidebarToggleBtn');
+
     // Initialize collection selector (always needed)
     collectionSelector = new CollectionSelector('collectionSelect', webdavClient);
     await collectionSelector.load();
@@ -321,7 +324,8 @@ document.addEventListener('DOMContentLoaded', async () => {
     editor.setWebDAVClient(webdavClient);
 
     // Initialize file tree (needed in both modes)
-    fileTree = new FileTree('fileTree', webdavClient);
+    // Pass isEditMode to control image filtering (hide images only in view mode)
+    fileTree = new FileTree('fileTree', webdavClient, isEditMode);
     fileTree.onFileSelect = async (item) => {
         try {
             const currentCollection = collectionSelector.getCurrentCollection();
@@ -579,6 +583,22 @@ document.addEventListener('DOMContentLoaded', async () => {
         await autoLoadPageInViewMode();
     }
 
+    // Setup clickable navbar brand (logo/title)
+    const navbarBrand = document.getElementById('navbarBrand');
+    if (navbarBrand) {
+        navbarBrand.addEventListener('click', (e) => {
+            e.preventDefault();
+            const currentCollection = collectionSelector ? collectionSelector.getCurrentCollection() : null;
+            if (currentCollection) {
+                // Navigate to collection root
+                window.location.href = `/${currentCollection}/`;
+            } else {
+                // Navigate to home page
+                window.location.href = '/';
+            }
+        });
+    }
+
     // Initialize mermaid (always needed)
     mermaid.initialize({ startOnLoad: true, theme: darkMode.isDark ? 'dark' : 'default' });
     // Listen for file-saved event to reload file tree