fix(hub): a track with no artist tag reaches the Music grid

The grid's unit is an album, so a track whose artist tag is empty was
drawn nowhere — while `empty` counted it and stayed false, so no message
appeared either. An untagged library rendered a toolbar over a blank
page, with every track one mode-switch away and nothing saying so.

It gets a card, the same shape the singleton folding already mints. No
cover is looked up for it, or for any album this file invented: the
release name is one the browser wrote, and the request cannot match.

music_untagged_probe.py renders the real grid and reads the page back.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

10 files changed, 10 insertions, 0 deletions

diff --git a/packages/meshbay-hub/src/meshbay_hub/static/locales/de.js b/packages/meshbay-hub/src/meshbay_hub/static/locales/de.js
index 2d925e1..aea1196 100644
--- a/packages/meshbay-hub/src/meshbay_hub/static/locales/de.js
+++ b/packages/meshbay-hub/src/meshbay_hub/static/locales/de.js
@@ -302,6 +302,7 @@ export default {
   'music.mode_flat': 'Flache Liste',
   'music.empty': 'Keine Musik gefunden.',
   'music.unknown_album': 'Unbekanntes Album',
+  'music.unknown_artist': 'Unbekannter Künstler',
   'music.various': 'Verschiedenes',
   'music.play_all': 'Alle abspielen',
   'music.menu_more': 'Mehr…',
diff --git a/packages/meshbay-hub/src/meshbay_hub/static/locales/en.js b/packages/meshbay-hub/src/meshbay_hub/static/locales/en.js
index 690a70b..d9172a6 100644
--- a/packages/meshbay-hub/src/meshbay_hub/static/locales/en.js
+++ b/packages/meshbay-hub/src/meshbay_hub/static/locales/en.js
@@ -300,6 +300,7 @@ export default {
   'music.mode_flat': 'Flat list',
   'music.empty': 'No music found.',
   'music.unknown_album': 'Unknown album',
+  'music.unknown_artist': 'Unknown artist',
   'music.various': 'Various',
   'music.play_all': 'Play all',
   'music.menu_more': 'More…',
diff --git a/packages/meshbay-hub/src/meshbay_hub/static/locales/es.js b/packages/meshbay-hub/src/meshbay_hub/static/locales/es.js
index c48f942..fc0e639 100644
--- a/packages/meshbay-hub/src/meshbay_hub/static/locales/es.js
+++ b/packages/meshbay-hub/src/meshbay_hub/static/locales/es.js
@@ -300,6 +300,7 @@ export default {
   'music.mode_flat': 'Lista plana',
   'music.empty': 'No se encontró música.',
   'music.unknown_album': 'Álbum desconocido',
+  'music.unknown_artist': 'Artista desconocido',
   'music.various': 'Varios',
   'music.play_all': 'Reproducir todo',
   'music.menu_more': 'Más…',
diff --git a/packages/meshbay-hub/src/meshbay_hub/static/locales/fr.js b/packages/meshbay-hub/src/meshbay_hub/static/locales/fr.js
index 6d148d6..5eb8d60 100644
--- a/packages/meshbay-hub/src/meshbay_hub/static/locales/fr.js
+++ b/packages/meshbay-hub/src/meshbay_hub/static/locales/fr.js
@@ -301,6 +301,7 @@ export default {
   'music.mode_flat': 'Liste à plat',
   'music.empty': 'Aucune musique trouvée.',
   'music.unknown_album': 'Album inconnu',
+  'music.unknown_artist': 'Artiste inconnu',
   'music.various': 'Divers',
   'music.play_all': 'Tout lire',
   'music.menu_more': 'Plus…',
diff --git a/packages/meshbay-hub/src/meshbay_hub/static/locales/it.js b/packages/meshbay-hub/src/meshbay_hub/static/locales/it.js
index c619d61..6d12cb3 100644
--- a/packages/meshbay-hub/src/meshbay_hub/static/locales/it.js
+++ b/packages/meshbay-hub/src/meshbay_hub/static/locales/it.js
@@ -301,6 +301,7 @@ export default {
   'music.mode_flat': 'Elenco semplice',
   'music.empty': 'Nessuna musica trovata.',
   'music.unknown_album': 'Album sconosciuto',
+  'music.unknown_artist': 'Artista sconosciuto',
   'music.various': 'Vari',
   'music.play_all': 'Riproduci tutto',
   'music.menu_more': 'Altro…',
diff --git a/packages/meshbay-hub/src/meshbay_hub/static/locales/ja.js b/packages/meshbay-hub/src/meshbay_hub/static/locales/ja.js
index eac90dc..f4ced88 100644
--- a/packages/meshbay-hub/src/meshbay_hub/static/locales/ja.js
+++ b/packages/meshbay-hub/src/meshbay_hub/static/locales/ja.js
@@ -298,6 +298,7 @@ export default {
   'music.mode_flat': 'フラットリスト',
   'music.empty': '音楽が見つかりません。',
   'music.unknown_album': '不明なアルバム',
+  'music.unknown_artist': '不明なアーティスト',
   'music.various': 'その他',
   'music.play_all': 'すべて再生',
   'music.menu_more': 'その他…',
diff --git a/packages/meshbay-hub/src/meshbay_hub/static/locales/nl.js b/packages/meshbay-hub/src/meshbay_hub/static/locales/nl.js
index 65bf4f5..31a2321 100644
--- a/packages/meshbay-hub/src/meshbay_hub/static/locales/nl.js
+++ b/packages/meshbay-hub/src/meshbay_hub/static/locales/nl.js
@@ -302,6 +302,7 @@ export default {
   'music.mode_flat': 'Platte lijst',
   'music.empty': 'Geen muziek gevonden.',
   'music.unknown_album': 'Onbekend album',
+  'music.unknown_artist': 'Onbekende artiest',
   'music.various': 'Diversen',
   'music.play_all': 'Alles afspelen',
   'music.menu_more': 'Meer…',
diff --git a/packages/meshbay-hub/src/meshbay_hub/static/locales/pl.js b/packages/meshbay-hub/src/meshbay_hub/static/locales/pl.js
index 264d442..463a6a9 100644
--- a/packages/meshbay-hub/src/meshbay_hub/static/locales/pl.js
+++ b/packages/meshbay-hub/src/meshbay_hub/static/locales/pl.js
@@ -309,6 +309,7 @@ export default {
   'music.mode_flat': 'Lista płaska',
   'music.empty': 'Nie znaleziono muzyki.',
   'music.unknown_album': 'Nieznany album',
+  'music.unknown_artist': 'Nieznany wykonawca',
   'music.various': 'Różne',
   'music.play_all': 'Odtwórz wszystko',
   'music.menu_more': 'Więcej…',
diff --git a/packages/meshbay-hub/src/meshbay_hub/static/locales/pt-BR.js b/packages/meshbay-hub/src/meshbay_hub/static/locales/pt-BR.js
index 0fbfb1e..20822ee 100644
--- a/packages/meshbay-hub/src/meshbay_hub/static/locales/pt-BR.js
+++ b/packages/meshbay-hub/src/meshbay_hub/static/locales/pt-BR.js
@@ -302,6 +302,7 @@ export default {
   'music.mode_flat': 'Lista simples',
   'music.empty': 'Nenhuma música encontrada.',
   'music.unknown_album': 'Álbum desconhecido',
+  'music.unknown_artist': 'Artista desconhecido',
   'music.various': 'Diversos',
   'music.play_all': 'Reproduzir tudo',
   'music.menu_more': 'Mais…',
diff --git a/packages/meshbay-hub/src/meshbay_hub/static/locales/zh-CN.js b/packages/meshbay-hub/src/meshbay_hub/static/locales/zh-CN.js
index ab75b11..b2d7591 100644
--- a/packages/meshbay-hub/src/meshbay_hub/static/locales/zh-CN.js
+++ b/packages/meshbay-hub/src/meshbay_hub/static/locales/zh-CN.js
@@ -295,6 +295,7 @@ export default {
   'music.mode_flat': '平铺列表',
   'music.empty': '未找到音乐。',
   'music.unknown_album': '未知专辑',
+  'music.unknown_artist': '未知艺术家',
   'music.various': '其他',
   'music.play_all': '全部播放',
   'music.menu_more': '更多…',