feat(lotto): backtest_runs/winner_calibration 테이블 + CRUD

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

lotto/tests/test_backtest_db.py

@@ -0,0 +1,31 @@
+import os, tempfile
+
+def _fresh_db(monkeypatch):
+    tmp = tempfile.mkdtemp()
+    path = os.path.join(tmp, "lotto.db")
+    from app import db
+    monkeypatch.setattr(db, "DB_PATH", path)
+    db.init_db()
+    return db
+
+def test_backtest_tables_exist(monkeypatch):
+    db = _fresh_db(monkeypatch)
+    with db._conn() as conn:
+        tables = {r["name"] for r in conn.execute(
+            "SELECT name FROM sqlite_master WHERE type='table'").fetchall()}
+    assert "backtest_runs" in tables
+    assert "winner_calibration" in tables
+
+def test_backtest_runs_unique(monkeypatch):
+    db = _fresh_db(monkeypatch)
+    db.save_backtest_run(draw_no=100, strategy="random_null", weight_label="-",
+                         weight_json=None, trial_id=None, n_tickets=10,
+                         hist={"m3":1,"m4":0,"m5":0,"m6":0,"bonus_hits":0},
+                         best_match=3, avg_meta_score=0.5)
+    db.save_backtest_run(draw_no=100, strategy="random_null", weight_label="-",
+                         weight_json=None, trial_id=None, n_tickets=10,
+                         hist={"m3":2,"m4":0,"m5":0,"m6":0,"bonus_hits":0},
+                         best_match=3, avg_meta_score=0.6)  # 멱등 upsert
+    rows = db.get_backtest_runs(draw_no=100)
+    assert len(rows) == 1
+    assert rows[0]["m3"] == 2  # 마지막 값으로 갱신