feat(web-player): rebuild Inicio and Buscar to the design handoff

Applies the handoff's layout and image shapes while keeping the current
Musify design system (Inter, colors, tokens) — no font or palette swap.

Inicio now stacks distinct shelves instead of repeated square grids:
recently played rows, a rail of recently listened albums with an "Álbum"
badge, a "Hecho para ti" bento of mixes, a rail of playlists with a
trailing dashed "Ver todas" tile, tall "Canciones nuevas" posters with a
"Nuevo" badge, a rail of circular top-artist avatars, and a recommended
rail. Buscar splits into Álbumes (square cards + badge), Usuarios (a
circular-avatar directory) and a flat Canciones list.

Top artists and the search user directory are filler data until the
backend exposes them. New shared pieces: Rail, CoverBadge, ArtistAvatar,
MixBentoTile. The orphaned TrackTile and MixCard are removed.

web-player/src/lib/server/userDirectory.ts

@@ -0,0 +1,24 @@
+export interface DirectoryUser {
+	id: string;
+	name: string;
+	handle: string;
+}
+
+const DIRECTORY: DirectoryUser[] = [
+	{ id: 'u1', name: 'Alex Rivera', handle: 'alexrivera' },
+	{ id: 'u2', name: 'Marina Cordero', handle: 'marinac' },
+	{ id: 'u3', name: 'Diego Fuentes', handle: 'dfuentes' },
+	{ id: 'u4', name: 'Lucía Marés', handle: 'luciamares' },
+	{ id: 'u5', name: 'Noah Bennett', handle: 'noahb' },
+	{ id: 'u6', name: 'Sara Ibáñez', handle: 'saraib' },
+	{ id: 'u7', name: 'Kairo', handle: 'kairo' },
+	{ id: 'u8', name: 'Valentina Ortiz', handle: 'valen' }
+];
+
+export function searchUsers(query: string, limit = 12): DirectoryUser[] {
+	const term = query.trim().toLowerCase();
+	if (!term) return [];
+	return DIRECTORY.filter(
+		(user) => user.name.toLowerCase().includes(term) || user.handle.toLowerCase().includes(term)
+	).slice(0, limit);
+}