feat(signal_v2-phase3a): config + state extensions for KIS data

- config.py: KIS_APP_KEY/SECRET/ACCOUNT/IS_VIRTUAL + V1_TOKEN_PATH env
- state.py: PollState extended with minute_bars (deque) and asking_price
- requirements.txt: websockets>=12

19 existing tests still pass.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

signal_v2/state.py

@@ -1,4 +1,5 @@
 """PollState — process-wide singleton."""
+from collections import deque
 from dataclasses import dataclass, field
 
 
@@ -7,9 +8,11 @@ class PollState:
     portfolio: dict | None = None
     news_sentiment: dict | None = None
     screener_preview: dict | None = None
+    # Phase 3a additions
+    minute_bars: dict[str, deque] = field(default_factory=dict)
+    asking_price: dict[str, dict] = field(default_factory=dict)
     last_updated: dict[str, str] = field(default_factory=dict)
     fetch_errors: dict[str, int] = field(default_factory=dict)
 
 
-# Process-wide singleton. Phase 3 imports: from signal_v2.state import state
 state = PollState()