full app is using live data now,

app/gunbuilder/page.tsx

@@ -8,11 +8,9 @@ import type { CategoryId, Part } from "@/types/gunbuilder";
 import { CategoryColumn } from "@/components/CategoryColumn";
 
 type GunbuilderProductFromApi = {
-  id: number;
-  uuid: string;
-  slug: string;
+  id: number;                 // backend numeric id
   name: string;
-  brandName: string;
+  brand: string;
   platform: string;
   partRole: string;
   price: number | null;
@@ -24,7 +22,6 @@ const API_BASE_URL =
   process.env.NEXT_PUBLIC_API_BASE_URL ?? "http://localhost:8080";
 
 // Map backend partRole to your existing CategoryId values.
-// Make sure these string values match the `id` fields in CATEGORIES.
 const PART_ROLE_TO_CATEGORY: Record<string, CategoryId> = {
   "upper-receiver": "upper" as CategoryId,
   barrel: "barrel" as CategoryId,
@@ -46,7 +43,6 @@ export default function GunbuilderPage() {
   const [loading, setLoading] = useState(true);
   const [error, setError] = useState<string | null>(null);
   const [build, setBuild] = useState<BuildState>(() => {
-    // Initialize from localStorage if available
     if (typeof window !== "undefined") {
       const stored = localStorage.getItem(STORAGE_KEY);
       if (stored) {
@@ -80,7 +76,7 @@ export default function GunbuilderPage() {
         const data: GunbuilderProductFromApi[] = await res.json();
 
         const normalized: Part[] = data
-          .map((p) => {
+          .map((p): Part | null => {
             const categoryId = PART_ROLE_TO_CATEGORY[p.partRole];
             if (!categoryId) {
               // Skip any parts we don't know how to map yet
@@ -88,17 +84,17 @@ export default function GunbuilderPage() {
             }
 
             return {
-              // Use the backend UUID as the stable id for the UI
-              id: p.uuid,
+              id: String(p.id), // <<< ALWAYS string
               categoryId,
               name: p.name,
-              brand: p.brandName,
+              brand: p.brand,
               price: p.price ?? 0,
               imageUrl: p.mainImageUrl ?? undefined,
               url: p.buyUrl ?? undefined,
-            } as Part;
+              notes: undefined,
+            };
           })
-          .filter(Boolean) as Part[];
+          .filter((p): p is Part => p !== null);
 
         setParts(normalized);
       } catch (err: any) {
@@ -114,7 +110,7 @@ export default function GunbuilderPage() {
     return () => controller.abort();
   }, []);
 
-  // Handle URL query parameter for part selection
+  // Handle URL query parameter for part selection (?select=upper:165)
   useEffect(() => {
     const selectParam = searchParams.get("select");
     if (selectParam) {
@@ -123,13 +119,12 @@ export default function GunbuilderPage() {
         setBuild((prev) => {
           const updated = {
             ...prev,
-            [categoryId]: partId,
+            [categoryId as CategoryId]: partId,
           };
-          // Persist to localStorage
           localStorage.setItem(STORAGE_KEY, JSON.stringify(updated));
           return updated;
         });
-        // Remove query param from URL
+
         router.replace("/gunbuilder", { scroll: false });
       }
     }
@@ -319,4 +314,4 @@ export default function GunbuilderPage() {
       </div>
     </main>
   );
-}
+}