feat(nav): merge Random Mix & Albums into Build a Mix hub

Replaces two sidebar entries (Random Mix, Random Albums) with a single 'Build a Mix' item (Wand2 icon) at /random. Landing page shows two cards — Mix by Tracks and Mix by Albums — with glow-on-hover. Old routes updated throughout. All 7 locales updated.

src/locales/nb.ts

@@ -5,6 +5,7 @@ export const nbTranslation = {
     newReleases: 'Nye utgivelser',
     allAlbums: 'Alle album',
     randomAlbums: 'Tilfeldige album',
+    randomPicker: 'Lag en miks',
     artists: 'Artister',
     randomMix: 'Tilfeldig miks',
     favorites: 'Favoritter',
@@ -203,6 +204,13 @@ export const nbTranslation = {
     removeSong: 'Fjern fra favoritter',
 	stations: 'Radiostasjoner',
   },
+  randomLanding: {
+    title: 'Lag en miks',
+    mixByTracks: 'Miks etter spor',
+    mixByTracksDesc: 'Tilfeldig utvalg av spor fra hele biblioteket ditt',
+    mixByAlbums: 'Miks etter album',
+    mixByAlbumsDesc: 'Tilfeldige album for nye oppdagelser',
+  },
   randomAlbums: {
     title: 'Tilfeldige album',
     refresh: 'Oppdater',