audit+fix: anti-look-ahead audit, migrate deployable config to >=12h

- trackD_lookahead_audit.py: relabel test (left==right, no labeling leak) + execution-lag
  stress -> our trend pipeline is CLEAN (4h Sharpe 1.36 robust to +1 bar lag, label-invariant)
- ADOPT conservative conclusion: deploy at 12h (sub-12h: costs/overfit dominate, slight Sharpe
  bump unreliable). 12h: Sharpe 1.32, DD 13.3%, CAGR 16.2% ~ identical and robust
- trend_portfolio: DEPLOY_TF=12h, resample_tf(rule); paper trader + tests on 12h
- calendar research (NEGATIVE, both): trackF seasonality (spurious), trackG prior-levels
  (breakouts continue, fade dead; only long-drift survivor, redundant with TP01)
- gitignore data/paper_trend runtime state

data/paper_trend/state.json

@@ -1,13 +0,0 @@
-{
-  "capital": 2000.0,
-  "initial_capital": 2000.0,
-  "start_ts": 1781884800000,
-  "last_ts": 1781884800000,
-  "positions": {
-    "BTC": 0.0,
-    "ETH": 0.0
-  },
-  "n_bars": 0,
-  "peak": 2000.0,
-  "max_dd": 0.0
-}