feat: add public listing catalog boundary

apps/api/src/modules/listings/repositories/listing-repository.js

@@ -121,6 +121,21 @@ export function createListingRepository(db) {
       };
     },
 
+    async findPublicById(listingId) {
+      const [result] = await db
+        .select({ listing: listings })
+        .from(listings)
+        .innerJoin(inventoryItems, eq(inventoryItems.id, listings.inventoryItemId))
+        .innerJoin(products, eq(products.id, inventoryItems.productId))
+        .where(and(
+          eq(listings.id, listingId),
+          inArray(listings.status, ['AVAILABLE', 'PENDING']),
+          eq(inventoryItems.status, 'ACTIVE'),
+        ));
+
+      return result?.listing ?? null;
+    },
+
     async updateStatus(listingId, status) {
       const [updatedListing] = await db
         .update(listings)

apps/api/src/modules/listings/routes/public-listing-routes.js

@@ -0,0 +1,32 @@
+import { toPublicListingDto } from '@pokemon-inventory/contracts/public-listing';
+
+function coerceNumber(value, fallback) {
+  if (value === undefined || value === null || value === '') {
+    return fallback;
+  }
+
+  const parsed = Number.parseInt(String(value), 10);
+  return Number.isNaN(parsed) ? fallback : parsed;
+}
+
+export async function registerPublicListingRoutes(app, options) {
+  const { publicListingService } = options;
+
+  app.get('/public/listings', async (request) => {
+    const result = await publicListingService.list({
+      page: coerceNumber(request.query.page, 1),
+      limit: coerceNumber(request.query.limit, 20),
+    });
+
+    return {
+      data: {
+        ...result,
+        items: result.items.map(toPublicListingDto),
+      },
+    };
+  });
+
+  app.get('/public/listings/:id', async (request) => ({
+    data: toPublicListingDto(await publicListingService.getById(request.params.id)),
+  }));
+}

apps/api/src/modules/listings/services/public-listing-service.js

@@ -0,0 +1,23 @@
+import { createApplicationError } from '../../../shared/errors/application-error.js';
+
+export function createPublicListingService({ listingRepository }) {
+  return {
+    async list(input = {}) {
+      return listingRepository.searchPublic({
+        query: '',
+        page: input.page,
+        limit: input.limit,
+      });
+    },
+
+    async getById(listingId) {
+      const listing = await listingRepository.findPublicById(listingId);
+
+      if (!listing) {
+        throw createApplicationError('LISTING_NOT_FOUND', 'Listing was not found.', 404);
+      }
+
+      return listing;
+    },
+  };
+}