Product filter implementation works correctly

Filters that display but do not narrow the list, or that OR across types instead of AND, return products that violate the shopper's explicit constraints — a $0-$50 selection that still shows $120 items destroys trust on the spot. Users correlate broken filters with a broken store and leave. Faceted navigation that ignores query parameters also generates duplicate-content SEO penalties because every filter URL serves the same full catalog.

Build the where clause conditionally so each active filter narrows the result set with AND semantics, and make sure price bounds use gte/lte rather than OR. Place the logic in src/app/api/products/route.ts:

let query: any = {}
if (categoryFilter) {
  query.categories = { some: { id: { in: categoryFilter } } }
}
if (priceMin && priceMax) {
  query.price = { gte: priceMin, lte: priceMax }
}
const results = await prisma.product.findMany({ where: query })