feat(media): complete mvp1 media foundation workflows

packages/db/prisma/seed.ts

@@ -13,6 +13,75 @@ async function main() {
     },
   })
 
+  const media = await db.mediaAsset.upsert({
+    where: { storageKey: "seed/artwork-welcome.jpg" },
+    update: {},
+    create: {
+      type: "artwork",
+      title: "Seed Artwork Image",
+      altText: "Seed artwork placeholder",
+      tags: ["seed", "portfolio"],
+      storageKey: "seed/artwork-welcome.jpg",
+      mimeType: "image/jpeg",
+      isPublished: true,
+    },
+  })
+
+  const artwork = await db.artwork.upsert({
+    where: { slug: "seed-artwork-welcome" },
+    update: {},
+    create: {
+      title: "Seed Artwork",
+      slug: "seed-artwork-welcome",
+      description: "Baseline seeded artwork for MVP1 media foundation.",
+      medium: "Digital",
+      year: 2026,
+      availability: "available",
+      isPublished: true,
+    },
+  })
+
+  const gallery = await db.gallery.upsert({
+    where: { slug: "featured" },
+    update: {},
+    create: {
+      name: "Featured",
+      slug: "featured",
+      description: "Featured artwork selection.",
+      isVisible: true,
+    },
+  })
+
+  await db.artworkGallery.upsert({
+    where: {
+      artworkId_galleryId: {
+        artworkId: artwork.id,
+        galleryId: gallery.id,
+      },
+    },
+    create: {
+      artworkId: artwork.id,
+      galleryId: gallery.id,
+    },
+    update: {},
+  })
+
+  await db.artworkRendition.upsert({
+    where: {
+      artworkId_slot: {
+        artworkId: artwork.id,
+        slot: "thumbnail",
+      },
+    },
+    create: {
+      artworkId: artwork.id,
+      mediaAssetId: media.id,
+      slot: "thumbnail",
+      isPrimary: true,
+    },
+    update: {},
+  })
+
   await db.systemSetting.upsert({
     where: { key: "public.header_banner" },
     update: {},