Add reference size fields to product admin editor

- Add referenceWidthCm and referenceHeightCm to ProductDTO
- Update toProductDTO to include reference size fields
- Add reference size inputs to admin product edit page
- Update updateProduct action to handle reference sizes
- Rulers on personalization page use product reference size

Co-Authored-By: Claude Haiku 4.5 <noreply@anthropic.com>

src/lib/product.ts

@@ -21,6 +21,8 @@ export function toProductDTO(p: PrismaProduct, activePromotions: ActivePromotion
     printAreaBack: p.printAreaBack ? JSON.parse(p.printAreaBack) : null,
     printAreaWidthMm: p.printAreaWidthMm,
     printAreaHeightMm: p.printAreaHeightMm,
+    referenceWidthCm: p.referenceWidthCm,
+    referenceHeightCm: p.referenceHeightCm,
     imageUrl: p.imageUrl,
     imageUrlBack: p.imageUrlBack,
     photoRecolorable: p.photoRecolorable,

src/lib/types.ts

@@ -45,6 +45,8 @@ export type ProductDTO = {
   printAreaBack: PrintArea | null;
   printAreaWidthMm: number;
   printAreaHeightMm: number;
+  referenceWidthCm: number | null;
+  referenceHeightCm: number | null;
   imageUrl: string | null;
   imageUrlBack: string | null;
   photoRecolorable: boolean;