FDR and pykrx APIs are currently blocked by KRX servers.
Added Naver Finance scraping (KOSPI + KOSDAQ market cap ranking)
as secondary source before falling back to hardcoded universe.
Fallback chain: FDR → Naver Finance (720+ stocks) → Hardcoded (86 stocks)
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>