fix(ai_news): escape MarkdownV2 reserved chars in score (+, -, .)

stock-lab/app/screener/ai_news/telegram.py

@@ -19,9 +19,10 @@ def _cost_won(tokens_input: int, tokens_output: int) -> int:
 
 def _row_line(idx: int, r: Dict[str, Any]) -> str:
     score = r["score_raw"]
-    sign = "+" if score >= 0 else ""
+    # score 문자열 자체를 _escape 통과 — '+', '-', '.' 모두 MarkdownV2 reserved
+    score_str = _escape(f"{score:+.1f}")
     return (
-        f"{idx}\\. {_escape(r['ticker'])} \\({sign}{score:.1f}\\) — "
+        f"{idx}\\. {_escape(r['ticker'])} \\({score_str}\\) — "
         f"{_escape(r['reason'])}"
     )