fix(catalog): make the Builder Club catalog read and write its own offers

The previous commit taught bulk editing and delete-with-restore about the BC
catalog. Neither actually worked, and one of them was destructive.

`catalog_items_bc` has six columns: id, item_ids, page_id, catalog_name,
order_number, extradata. There is no price, points, currency, offer_id, limit or
membership column on it. The bulk path read and wrote columns that do not
exist, and the UPDATE was aimed at catalog_items while the SELECT came from
catalog_items_bc — so a BC category move wrote into the normal catalog. Two
tests now pin that pairing: reads and writes have to stay in the same table.

Underneath it the BC table was never being read at all. The inline editor
fetched `/api/admin/catalog/items?pageId=N` without the catalog, so opening a BC
category showed the normal catalog's offers, and the route selected BC rows
directly instead of going through the loader, skipping the furni enrichment the
table needs to render anything but a bare caption. Both catalogs now take the
same path, and the catalog is in the fetch callback's dependencies — without
that, a switch keeps reading the previous catalog's rows through a stale
closure.

Because a BC offer has no price, the editor no longer offers one. The server
refuses price, points and currency changes with a readable message instead of
letting them reach the database as an unknown-column error, and a BC bulk edit
is what it can actually be: a category move.

BC deletions also went through a bare DELETE, which made them the one catalog
mutation with no way back. They now keep their rows and hand back a restoreId
like the normal ones. The catalog is recorded in the audit target rather than
in the payload, so a restore can never put a BC row into the normal offers
table.

src/app/api/admin/catalog/items/route.ts

@@ -1,16 +1,8 @@
-import { asc, eq } from "drizzle-orm";
 import { apiError, apiOk } from "@/lib/api";
 import { withAdmin } from "@/lib/api-handler";
-import { CatalogItemsBc, db } from "@/lib/db";
 import { PERMS } from "@/lib/permissions";
 import { loadCatalogItemsData } from "@/lib/services/catalog-items-loader";
 
-function jsonSafe<T>(data: T): T {
-	return JSON.parse(
-		JSON.stringify(data, (_k, v) => (typeof v === "bigint" ? Number(v) : v)),
-	) as T;
-}
-
 export const GET = withAdmin(
 	{ permission: PERMS.CATALOG_VIEW },
 	async (request) => {
@@ -18,16 +10,16 @@ export const GET = withAdmin(
 		if (!Number.isFinite(pageId) || pageId <= 0) {
 			return apiError("Invalid pageId");
 		}
-		const isBc = request.nextUrl.searchParams.get("catalog") === "bc";
-		if (isBc) {
-			const items = await db
-				.select()
-				.from(CatalogItemsBc)
-				.where(eq(CatalogItemsBc.pageId, pageId))
-				.orderBy(asc(CatalogItemsBc.orderNumber));
-			return apiOk({ items: jsonSafe(items) });
-		}
-		const data = await loadCatalogItemsData(pageId);
-		return apiOk(jsonSafe(data) as unknown as Record<string, unknown>);
+		const catalog =
+			request.nextUrl.searchParams.get("catalog") === "bc" ? "bc" : "normal";
+		// Both catalogs go through the loader. The BC branch used to select the
+		// rows directly, which returned them without the furni enrichment the
+		// table needs to render anything but a bare caption.
+		return apiOk(
+			(await loadCatalogItemsData(pageId, catalog)) as unknown as Record<
+				string,
+				unknown
+			>,
+		);
 	},
 );