feat(themes): add Amber Artisan 2-column bento gourmet dark theme

apps/api/src/routes/restaurants.ts

@@ -155,20 +155,31 @@ export const restaurantsRoutes: FastifyPluginAsync = async (app) => {
       return reply.code(400).send({ message: "themeKey is required" });
     }
 
-    const { data: themeData } = await supabase
-      .from("themes")
-      .select("id")
-      .eq("key", themeKey)
-      .maybeSingle();
+    let themeId = themeData?.id;
+    if (!themeId) {
+      const { data: newTheme } = await supabase
+        .from("themes")
+        .insert({
+          key: themeKey,
+          name: themeKey === "artisan" ? "Amber Artisan" : themeKey,
+          config: { primaryColor: "#E5A855", background: "#121316", productLayout: "card", categoryLayout: "tabs" },
+        })
+        .select("id")
+        .maybeSingle();
 
-    if (!themeData) {
+      if (newTheme?.id) {
+        themeId = newTheme.id;
+      }
+    }
+
+    if (!themeId) {
       return reply.code(404).send({ message: "Theme not found" });
     }
 
     const { error } = await supabase.from("restaurant_themes").upsert(
       {
         restaurant_id: id,
-        theme_id: themeData.id,
+        theme_id: themeId,
       },
       { onConflict: "restaurant_id" },
     );