feat(provenance): always-on artist label on gallery thumbnails

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

frontend/src/components/gallery/GalleryItem.vue

@@ -25,6 +25,14 @@
         </div>
         <div v-if="selected" class="fc-gallery-item__order">{{ orderNum }}</div>
       </template>
+      <div v-if="image.artist" class="fc-gallery-item__artist">
+        <RouterLink
+          v-if="!sel.isSelectMode"
+          :to="`/artist/${image.artist.slug}`"
+          @click.stop
+        >{{ image.artist.name }}</RouterLink>
+        <span v-else>{{ image.artist.name }}</span>
+      </div>
     </div>
   </v-card>
 </template>
@@ -107,4 +115,20 @@ function onThumbError() { thumbError.value = true }
   display: grid; place-items: center; z-index: 11;
   pointer-events: none;
 }
+.fc-gallery-item__artist {
+  position: absolute; left: 0; right: 0; bottom: 0;
+  padding: 14px 8px 6px;
+  background: linear-gradient(
+    to top, rgba(20, 23, 26, 0.78), rgba(20, 23, 26, 0)
+  );
+  font-size: 12px; line-height: 1.2;
+  white-space: nowrap; overflow: hidden; text-overflow: ellipsis;
+  pointer-events: none;
+}
+.fc-gallery-item__artist a {
+  color: rgb(var(--v-theme-parchment, 232 228 216));
+  text-decoration: none;
+  pointer-events: auto;
+}
+.fc-gallery-item__artist span { color: rgba(232, 228, 216, 0.85); }
 </style>