feat(albums): compilation filter toggle in All Albums

Tri-state button (all / only compilations / hide compilations) in the
Albums page header, using the OpenSubsonic isCompilation tag from
Navidrome. Client-side filter via useMemo, no extra server calls.
Closes #65.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/locales/nb.ts

@@ -290,6 +290,12 @@ export const nbTranslation = {
     yearTo: 'Til',
     yearFilterClear: 'Tøm år filteret',
     yearFilterLabel: 'År',
+    compilationLabel: 'Samleplater',
+    compilationOnly: 'Kun samleplater',
+    compilationHide: 'Skjul samleplater',
+    compilationTooltipAll: 'Alle album · klikk: kun samleplater',
+    compilationTooltipOnly: 'Kun samleplater · klikk: skjul samleplater',
+    compilationTooltipHide: 'Samleplater skjult · klikk: vis alle',
     select: 'Multivalg',
     startSelect: 'Aktiver multivalg',
     cancelSelect: 'Avbryt',