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/en/settings/labels.json

@@ -7,5 +7,9 @@
   "searchPlaceholder": "Search by name",
   "emptyText": "Labels can be created while updating or creating tasks.",
   "pinTooltip": "Click to pin this into the main menu",
-  "colorChangeTooltip": "Click to change color"
+  "colorChangeTooltip": "Click to change color",
+  "pageTitle": "Manage Labels",
+  "deleteConfirmTitle": "Are you sure you want to delete this?",
+  "deleteButton": "Delete",
+  "cancelButton": "Cancel"
 }