fix: download notification opened the wrong song (same-name album)

The finished-download notification resolved the album by name via search3, then fell back to
a same-named album by a DIFFERENT artist (or the first result) when the exact artist match
wasn't found — e.g. right after download, before Navidrome rescans. Many artists share an album
title ("I LIKE IT!"), so the notification navigated to a completely different song.

- Web (notify.js) + Android (AppNavigation): require the artist to match when known (fuzzy for
  multi-artist / album-artist drift); drop the name-only and first-result fallbacks. If nothing
  matches, show "wird evtl. gerade gescannt" instead of opening a wrong album.

The download itself was correct all along (verified: it grabbed UPSAHL's official "I LIKE IT!"
visualizer) — only the notification's navigation was wrong. SW ns-v63.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

android/app/src/main/kotlin/com/novasonic/app/ui/AppNavigation.kt

@@ -576,13 +576,19 @@ fun AppNavigation() {
                                     val res = repo.search(n.navAlbum)
                                     val albums = res.album
                                     val norm = { s: String -> s.lowercase().trim() }
+                                    val na = norm(n.navArtist)
+                                    // REQUIRE the artist match when we know it — several artists share an
+                                    // album title ("I LIKE IT!"); the old name-only / firstOrNull fallback
+                                    // opened a completely different artist's album (wrong song).
                                     val match = albums.firstOrNull {
-                                        norm(it.name) == norm(n.navAlbum) &&
-                                        (n.navArtist.isBlank() || norm(it.artist ?: "") == norm(n.navArtist))
-                                    } ?: albums.firstOrNull { norm(it.name) == norm(n.navAlbum) }
-                                      ?: albums.firstOrNull()
+                                        val aa = norm(it.artist ?: "")
+                                        norm(it.name) == norm(n.navAlbum) && na.isNotBlank() &&
+                                        (aa == na || aa.contains(na) || na.contains(aa))
+                                    } ?: if (na.isBlank()) albums.firstOrNull { norm(it.name) == norm(n.navAlbum) } else null
                                     if (match != null) {
                                         navController.navigate("album/${match.id}")
+                                    } else {
+                                        Toast.makeText(context, "Album noch nicht gefunden — evtl. wird die Library gerade gescannt", Toast.LENGTH_SHORT).show()
                                     }
                                 }
                             }