feat(hub): add open/close arrows on archive chart with continuous klines

Span chart window across hold period, fill 5m gaps for smooth aggregation, and mark entry/exit with lightweight-charts arrows.

Co-authored-by: Cursor <cursoragent@cursor.com>

tests/test_hub_symbol_archive_lib.py

@@ -7,6 +7,7 @@ from pathlib import Path
 
 from hub_ohlcv_lib import aggregate_ohlcv_bars
 from hub_symbol_archive_lib import (
+    _fill_missing_bars,
     init_db,
     resolve_archive_chart,
     upsert_bars_5m,
@@ -16,7 +17,15 @@ from hub_symbol_archive_lib import (
 )
 
 
-def _seed_5m_bars(db: Path, start_ms: int, count: int, step: int = 300_000) -> None:
+def _seed_5m_bars(
+    db: Path,
+    start_ms: int,
+    count: int,
+    step: int = 300_000,
+    *,
+    ex: str = "gate",
+    sym: str = "ONDO",
+) -> None:
     bars = []
     price = 1.0
     for i in range(count):
@@ -32,7 +41,7 @@ def _seed_5m_bars(db: Path, start_ms: int, count: int, step: int = 300_000) -> N
                 "volume": 100 + i,
             }
         )
-    upsert_bars_5m("gate", "ONDO", bars, db_path=db)
+    upsert_bars_5m(ex, sym, bars, db_path=db)
 
 
 def test_aggregate_15m_from_5m():
@@ -76,6 +85,53 @@ def test_resolve_archive_chart_15m():
         assert len(out["candles"]) >= 10
 
 
+def test_fill_missing_bars_continuity():
+    period = 300_000
+    start = (1_700_000_000_000 // period) * period
+    bars = [
+        {
+            "open_time_ms": start,
+            "open": 1.0,
+            "high": 1.1,
+            "low": 0.9,
+            "close": 1.05,
+            "volume": 10,
+        },
+        {
+            "open_time_ms": start + period * 2,
+            "open": 1.05,
+            "high": 1.15,
+            "low": 1.0,
+            "close": 1.1,
+            "volume": 8,
+        },
+    ]
+    filled = _fill_missing_bars(bars, period, start, start + period * 2)
+    assert len(filled) >= 3
+    assert any(b.get("filled") for b in filled)
+
+
+def test_resolve_archive_chart_hold_window():
+    with tempfile.TemporaryDirectory() as td:
+        db = Path(td) / "archive.db"
+        init_db(db)
+        open_ms = 1_700_000_000_000
+        close_ms = open_ms + 6 * 3600_000
+        _seed_5m_bars(db, open_ms - 20 * 300_000, 200, ex="gate", sym="BNB/USDT")
+        out = resolve_archive_chart(
+            "gate",
+            "BNB/USDT",
+            "15m",
+            opened_ms=open_ms,
+            closed_ms=close_ms,
+            mode="hold",
+            db_path=db,
+        )
+        assert out["ok"] is True
+        assert out.get("opened_ms") == open_ms
+        assert len(out["candles"]) >= 10
+
+
 def test_list_with_overlay_filters():
     with tempfile.TemporaryDirectory() as td:
         db = Path(td) / "archive.db"