Fix inconsistent capitalization of sort rule labels

Applied sorting rules and manual add buttons now consistently display
properly capitalized labels (e.g., "Release Date" instead of mixed cases).

Author: alexesprit

src/features/sorting/components/SortRulesList.tsx

@@ -80,7 +80,7 @@ function SortableRuleItem({
             <GripVertical className="w-4 h-4 text-zinc-600" />
           </button>
           <div className="inline-flex items-center rounded-full border border-transparent bg-zinc-800 text-zinc-50 px-2.5 py-0.5 text-xs font-semibold">
-            {label.charAt(0).toUpperCase() + label.slice(1)}
+            {label}
           </div>
         </div>
         <div className="flex items-center gap-2">

src/features/sorting/utils/sortRules.test.ts

@@ -158,34 +158,34 @@ describe('getSortKeyName', () => {
   test('should format artist key correctly', () => {
     const result = getSortKeyName('artist')
 
-    expect(result).toBe('artist')
+    expect(result).toBe('Artist')
   })
 
   test('should format album key correctly', () => {
     const result = getSortKeyName('album')
 
-    expect(result).toBe('album')
+    expect(result).toBe('Album')
   })
 
   test('should format release_date key correctly', () => {
     const result = getSortKeyName('release_date')
 
-    expect(result).toBe('release date')
+    expect(result).toBe('Release Date')
   })
 
   test('should format title key correctly', () => {
     const result = getSortKeyName('title')
 
-    expect(result).toBe('track title')
+    expect(result).toBe('Track Title')
   })
 
   test('should handle all sort keys', () => {
     const sortKeys: SortKey[] = ['artist', 'album', 'release_date', 'title']
     const expectedNames: Record<SortKey, string> = {
-      artist: 'artist',
-      album: 'album',
-      release_date: 'release date',
-      title: 'track title',
+      artist: 'Artist',
+      album: 'Album',
+      release_date: 'Release Date',
+      title: 'Track Title',
     }
 
     sortKeys.forEach((key) => {

src/features/sorting/utils/sortRules.ts

@@ -55,7 +55,7 @@ export function convertToRawSortRules(sortRules: SortRule[]): string {
  * @return Display name of the sort key
  */
 export function getSortKeyName(sortKey: SortKey): string {
-  return SORT_KEY_LABELS[sortKey].toLowerCase()
+  return SORT_KEY_LABELS[sortKey]
 }
 
 /* Internal */