feat(sync): trust Hiboutik answers for deletions

A successful (2xx) answer from Hiboutik is now the truth, even an empty
list: records missing from it are deleted. The "empty list means API
issue" safety nets are removed.

Deletion stays safe because a failed call deletes nothing: HTTP errors
throw, and the new HiboutikClient.getList (used by getAllPages and the
non-paginated lists) also throws on a 2xx body that is not a list, so a
malformed answer is never mistaken for an empty list. A 2xx without body
is an empty list.

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

src/hiboutik/stock.hiboutik.repository.ts

@@ -9,7 +9,7 @@ export class StockHiboutikRepository {
 
   /** Stock of every product and size, all warehouses combined. Not paginated. */
   async getStocks(): Promise<StockHiboutikDto[]> {
-    const stocks = await this.hiboutikClient.get<StockHiboutikDto[]>('/stock_available/all_wh', {});
+    const stocks = await this.hiboutikClient.getList<StockHiboutikDto>('/stock_available/all_wh', {});
     // Hiboutik may return ids as strings: normalize them so strict comparisons work downstream
     return stocks.map((stock) => ({
       ...stock,