feat(labels): implement label update functionality and enhance UI

- Added `updateLabel` method in `LabelsController` to handle label updates with validation for name and color.
- Updated API routes to include the new label update endpoint.
- Introduced `LabelsDrawer` component for editing labels, including a color picker and form validation.
- Enhanced localization files to support new UI strings for label management.
- Implemented a new `LabelsSettings` page to manage labels with search and edit capabilities.
- Improved color handling with a comprehensive color palette for better user experience.

worklenz-frontend/public/locales/zh/settings/labels.json

@@ -7,5 +7,9 @@
   "searchPlaceholder": "按名称搜索",
   "emptyText": "标签可以在更新或创建任务时创建。",
   "pinTooltip": "点击将其固定到主菜单",
-  "colorChangeTooltip": "点击更改颜色"
+  "colorChangeTooltip": "点击更改颜色",
+  "pageTitle": "管理标签",
+  "deleteConfirmTitle": "您确定要删除这个吗？",
+  "deleteButton": "删除",
+  "cancelButton": "取消"
 }