Summary

• add a GS25 store-search fallback that uses stock lookup when coordinate store search comes back empty
• pass the deployed Zyte API key through LotteMart API handlers and MCP tools
• cover the GS25 fallback and LotteMart default Zyte fallback paths in tests

Verification

• npm run format:check
• npm run lint
• npm run typecheck
• npm run build
• npx vitest run tests/services/gs25/tools/findNearbyStores.test.ts tests/services/lottemart/tools/findNearbyStores.test.ts tests/services/lottemart/tools/searchProducts.test.ts tests/api/gs25-handlers.test.ts tests/api/lottemart-handlers.test.ts
• npx vitest run tests/app/app-api-lottemart.test.ts tests/app/app-api-gs25.test.ts --testTimeout=30000
• npx vitest run --testTimeout=30000 --hookTimeout=30000

Refs #45, #46