fix: reduce F&G log noise and skip scan loop when blocked

- fng.py: downgrade per-ticker block log to DEBUG
- runner.py: skip entire scan (continue) when F&G < FNG_MIN_ENTRY
  instead of iterating 20 tickers each blocked individually

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

core/fng.py

@@ -67,5 +67,5 @@ def is_entry_allowed() -> bool:
             "공포" if fv <= 40 else
             "약공포"
         )
-        logger.info(f"[F&G] 진입 차단 — F&G={fv} ({label}) < {FNG_MIN_ENTRY}")
+        logger.debug(f"[F&G] 진입 차단 — F&G={fv} ({label}) < {FNG_MIN_ENTRY}")
     return allowed