feat: add collapsible settings panel and resizable notes list (v0.1.2)

- Settings panel in categories sidebar now collapses/expands with toggle button
- Settings collapsed by default to save space
- Notes list column now resizable with drag handle (240px-600px range)
- Improved UI flexibility and space management

src/components/CategoriesSidebar.tsx

@@ -58,6 +58,7 @@ export function CategoriesSidebar({
 }: CategoriesSidebarProps) {
   const [isCreating, setIsCreating] = useState(false);
   const [newCategoryName, setNewCategoryName] = useState('');
+  const [isSettingsCollapsed, setIsSettingsCollapsed] = useState(true);
   const inputRef = useRef<HTMLInputElement>(null);
 
   useEffect(() => {
@@ -185,27 +186,40 @@ export function CategoriesSidebar({
       </div>
 
       {/* User Info and Settings */}
-      <div className="border-t border-gray-200 dark:border-gray-700 p-4 bg-white dark:bg-gray-900">
-        <div className="flex items-center justify-between mb-3">
+      <div className="border-t border-gray-200 dark:border-gray-700 bg-white dark:bg-gray-900">
+        <div className="flex items-center justify-between p-4 pb-3">
           <div className="flex items-center space-x-2 min-w-0">
             <div className="w-8 h-8 bg-blue-500 rounded-full flex items-center justify-center text-white font-semibold flex-shrink-0">
               {username.charAt(0).toUpperCase()}
             </div>
             <span className="text-sm text-gray-700 dark:text-gray-200 truncate font-medium">{username}</span>
           </div>
-          <button
-            onClick={onLogout}
-            className="p-2 hover:bg-gray-100 dark:hover:bg-gray-700 rounded-lg transition-colors flex-shrink-0"
-            title="Logout"
-          >
-            <svg className="w-5 h-5 text-gray-600 dark:text-gray-300" fill="none" stroke="currentColor" viewBox="0 0 24 24">
-              <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M17 16l4-4m0 0l-4-4m4 4H7m6 4v1a3 3 0 01-3 3H6a3 3 0 01-3-3V7a3 3 0 013-3h4a3 3 0 013 3v1" />
-            </svg>
-          </button>
+          <div className="flex items-center gap-1">
+            <button
+              onClick={() => setIsSettingsCollapsed(!isSettingsCollapsed)}
+              className="p-2 hover:bg-gray-100 dark:hover:bg-gray-700 rounded-lg transition-colors flex-shrink-0"
+              title={isSettingsCollapsed ? "Show Settings" : "Hide Settings"}
+            >
+              <svg className={`w-4 h-4 text-gray-600 dark:text-gray-300 transition-transform ${isSettingsCollapsed ? 'rotate-180' : ''}`} fill="none" stroke="currentColor" viewBox="0 0 24 24">
+                <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M19 9l-7 7-7-7" />
+              </svg>
+            </button>
+            <button
+              onClick={onLogout}
+              className="p-2 hover:bg-gray-100 dark:hover:bg-gray-700 rounded-lg transition-colors flex-shrink-0"
+              title="Logout"
+            >
+              <svg className="w-5 h-5 text-gray-600 dark:text-gray-300" fill="none" stroke="currentColor" viewBox="0 0 24 24">
+                <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M17 16l4-4m0 0l-4-4m4 4H7m6 4v1a3 3 0 01-3 3H6a3 3 0 01-3-3V7a3 3 0 013-3h4a3 3 0 013 3v1" />
+              </svg>
+            </button>
+          </div>
         </div>
         
-        {/* Theme Toggle */}
-        <div className="flex items-center justify-between mb-3">
+        {!isSettingsCollapsed && (
+          <div className="px-4 pb-4">
+            {/* Theme Toggle */}
+            <div className="flex items-center justify-between mb-3">
           <span className="text-xs text-gray-500 dark:text-gray-400">Theme</span>
           <div className="flex items-center space-x-1 bg-gray-100 dark:bg-gray-700 rounded-lg p-1">
             <button
@@ -250,77 +264,79 @@ export function CategoriesSidebar({
           </div>
         </div>
 
-        {/* Font Settings */}
-        <div className="mt-4 pt-3 border-t border-gray-200 dark:border-gray-700 space-y-3">
+            {/* Font Settings */}
+            <div className="mt-4 pt-3 border-t border-gray-200 dark:border-gray-700 space-y-3">
           <span className="text-xs font-medium text-gray-500 dark:text-gray-400 uppercase tracking-wider">Fonts</span>
           
-          {/* Editor Font */}
-          <div className="bg-gray-50 dark:bg-gray-800 rounded-lg p-3">
-            <div className="flex items-center gap-2 mb-2">
-              <svg className="w-4 h-4 text-gray-500 dark:text-gray-400" fill="none" stroke="currentColor" viewBox="0 0 24 24">
-                <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M10 20l4-16m4 4l4 4-4 4M6 16l-4-4 4-4" />
-              </svg>
-              <span className="text-xs font-medium text-gray-600 dark:text-gray-300">Editor</span>
-            </div>
-            <div className="flex gap-2">
-              <select
-                value={editorFont}
-                onChange={(e) => onEditorFontChange(e.target.value)}
-                className="flex-1 min-w-0 text-sm px-3 py-1.5 bg-white dark:bg-gray-700 border border-gray-200 dark:border-gray-600 rounded-lg text-gray-700 dark:text-gray-200 focus:ring-2 focus:ring-blue-500 focus:border-transparent cursor-pointer"
-                style={{ fontFamily: editorFont }}
-              >
-                {EDITOR_FONTS.map((font) => (
-                  <option key={font.value} value={font.value} style={{ fontFamily: font.value }}>
-                    {font.name}
-                  </option>
-                ))}
-              </select>
-              <select
-                value={editorFontSize}
-                onChange={(e) => onEditorFontSizeChange(parseInt(e.target.value, 10))}
-                className="w-16 flex-shrink-0 text-sm px-2 py-1.5 bg-white dark:bg-gray-700 border border-gray-200 dark:border-gray-600 rounded-lg text-gray-700 dark:text-gray-200 focus:ring-2 focus:ring-blue-500 focus:border-transparent cursor-pointer text-center"
-              >
-                {[12, 13, 14, 15, 16, 17, 18, 20, 22, 24].map((size) => (
-                  <option key={size} value={size}>{size}</option>
-                ))}
-              </select>
-            </div>
-          </div>
+              {/* Editor Font */}
+              <div className="bg-gray-50 dark:bg-gray-800 rounded-lg p-3">
+                <div className="flex items-center gap-2 mb-2">
+                  <svg className="w-4 h-4 text-gray-500 dark:text-gray-400" fill="none" stroke="currentColor" viewBox="0 0 24 24">
+                    <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M10 20l4-16m4 4l4 4-4 4M6 16l-4-4 4-4" />
+                  </svg>
+                  <span className="text-xs font-medium text-gray-600 dark:text-gray-300">Editor</span>
+                </div>
+                <div className="flex gap-2">
+                  <select
+                    value={editorFont}
+                    onChange={(e) => onEditorFontChange(e.target.value)}
+                    className="flex-1 min-w-0 text-sm px-3 py-1.5 bg-white dark:bg-gray-700 border border-gray-200 dark:border-gray-600 rounded-lg text-gray-700 dark:text-gray-200 focus:ring-2 focus:ring-blue-500 focus:border-transparent cursor-pointer"
+                    style={{ fontFamily: editorFont }}
+                  >
+                    {EDITOR_FONTS.map((font) => (
+                      <option key={font.value} value={font.value} style={{ fontFamily: font.value }}>
+                        {font.name}
+                      </option>
+                    ))}
+                  </select>
+                  <select
+                    value={editorFontSize}
+                    onChange={(e) => onEditorFontSizeChange(parseInt(e.target.value, 10))}
+                    className="w-16 flex-shrink-0 text-sm px-2 py-1.5 bg-white dark:bg-gray-700 border border-gray-200 dark:border-gray-600 rounded-lg text-gray-700 dark:text-gray-200 focus:ring-2 focus:ring-blue-500 focus:border-transparent cursor-pointer text-center"
+                  >
+                    {[12, 13, 14, 15, 16, 17, 18, 20, 22, 24].map((size) => (
+                      <option key={size} value={size}>{size}</option>
+                    ))}
+                  </select>
+                </div>
+              </div>
 
-          {/* Preview Font */}
-          <div className="bg-gray-50 dark:bg-gray-800 rounded-lg p-3">
-            <div className="flex items-center gap-2 mb-2">
-              <svg className="w-4 h-4 text-gray-500 dark:text-gray-400" fill="none" stroke="currentColor" viewBox="0 0 24 24">
-                <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M15 12a3 3 0 11-6 0 3 3 0 016 0z" />
-                <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M2.458 12C3.732 7.943 7.523 5 12 5c4.478 0 8.268 2.943 9.542 7-1.274 4.057-5.064 7-9.542 7-4.477 0-8.268-2.943-9.542-7z" />
-              </svg>
-              <span className="text-xs font-medium text-gray-600 dark:text-gray-300">Preview</span>
-            </div>
-            <div className="flex gap-2">
-              <select
-                value={previewFont}
-                onChange={(e) => onPreviewFontChange(e.target.value)}
-                className="flex-1 min-w-0 text-sm px-3 py-1.5 bg-white dark:bg-gray-700 border border-gray-200 dark:border-gray-600 rounded-lg text-gray-700 dark:text-gray-200 focus:ring-2 focus:ring-blue-500 focus:border-transparent cursor-pointer"
-                style={{ fontFamily: previewFont }}
-              >
-                {PREVIEW_FONTS.map((font) => (
-                  <option key={font.value} value={font.value} style={{ fontFamily: font.value }}>
-                    {font.name}
-                  </option>
-                ))}
-              </select>
-              <select
-                value={previewFontSize}
-                onChange={(e) => onPreviewFontSizeChange(parseInt(e.target.value, 10))}
-                className="w-16 flex-shrink-0 text-sm px-2 py-1.5 bg-white dark:bg-gray-700 border border-gray-200 dark:border-gray-600 rounded-lg text-gray-700 dark:text-gray-200 focus:ring-2 focus:ring-blue-500 focus:border-transparent cursor-pointer text-center"
-              >
-                {[12, 13, 14, 15, 16, 17, 18, 20, 22, 24].map((size) => (
-                  <option key={size} value={size}>{size}</option>
-                ))}
-              </select>
+              {/* Preview Font */}
+              <div className="bg-gray-50 dark:bg-gray-800 rounded-lg p-3">
+                <div className="flex items-center gap-2 mb-2">
+                  <svg className="w-4 h-4 text-gray-500 dark:text-gray-400" fill="none" stroke="currentColor" viewBox="0 0 24 24">
+                    <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M15 12a3 3 0 11-6 0 3 3 0 016 0z" />
+                    <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M2.458 12C3.732 7.943 7.523 5 12 5c4.478 0 8.268 2.943 9.542 7-1.274 4.057-5.064 7-9.542 7-4.477 0-8.268-2.943-9.542-7z" />
+                  </svg>
+                  <span className="text-xs font-medium text-gray-600 dark:text-gray-300">Preview</span>
+                </div>
+                <div className="flex gap-2">
+                  <select
+                    value={previewFont}
+                    onChange={(e) => onPreviewFontChange(e.target.value)}
+                    className="flex-1 min-w-0 text-sm px-3 py-1.5 bg-white dark:bg-gray-700 border border-gray-200 dark:border-gray-600 rounded-lg text-gray-700 dark:text-gray-200 focus:ring-2 focus:ring-blue-500 focus:border-transparent cursor-pointer"
+                    style={{ fontFamily: previewFont }}
+                  >
+                    {PREVIEW_FONTS.map((font) => (
+                      <option key={font.value} value={font.value} style={{ fontFamily: font.value }}>
+                        {font.name}
+                      </option>
+                    ))}
+                  </select>
+                  <select
+                    value={previewFontSize}
+                    onChange={(e) => onPreviewFontSizeChange(parseInt(e.target.value, 10))}
+                    className="w-16 flex-shrink-0 text-sm px-2 py-1.5 bg-white dark:bg-gray-700 border border-gray-200 dark:border-gray-600 rounded-lg text-gray-700 dark:text-gray-200 focus:ring-2 focus:ring-blue-500 focus:border-transparent cursor-pointer text-center"
+                  >
+                    {[12, 13, 14, 15, 16, 17, 18, 20, 22, 24].map((size) => (
+                      <option key={size} value={size}>{size}</option>
+                    ))}
+                  </select>
+                </div>
+              </div>
             </div>
           </div>
-        </div>
+        )}
       </div>
     </div>
   );