feat: add public search controls

Add public category lookup options, allowlisted sort ordering, URL-backed catalog controls, and strict search route validation with regression tests.

apps/api/src/modules/search/domain/search-query.js

@@ -23,6 +23,7 @@ export function createSearchQuery({
   page = 1,
   limit = 20,
   includeSold = false,
+  sort = 'recent',
 }) {
   const text = normalizeSearchQuery(query);
 
@@ -50,6 +51,10 @@ export function createSearchQuery({
     throw new Error('minPriceMinor must be <= maxPriceMinor');
   }
 
+  if (!['recent', 'price_low', 'price_high'].includes(sort)) {
+    throw new Error('sort must be recent, price_low, or price_high');
+  }
+
   return {
     text,
     ...(typeof category === 'string' && category.trim().length > 0 ? { category: category.trim() } : {}),
@@ -58,6 +63,7 @@ export function createSearchQuery({
     page,
     limit,
     includeSold,
+    ...(sort !== 'recent' ? { sort } : {}),
   };
 }