Paginate review list (10/page); show open/close/hold duration in BJT.

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

app/db.py

@@ -247,12 +247,10 @@ def auth_token(conn: sqlite3.Connection, token: str) -> Optional[dict]:
     return row_to_dict(row)
 
 
-def list_trades(
-    conn: sqlite3.Connection,
-    limit: int = 200,
+def _trades_where(
     account_id: Optional[int] = None,
     machine_id: Optional[int] = None,
-) -> list[dict]:
+) -> tuple[str, list[Any]]:
     where: list[str] = []
     params: list[Any] = []
     if account_id is not None:
@@ -261,16 +259,39 @@ def list_trades(
     if machine_id is not None:
         where.append("t.machine_id=?")
         params.append(machine_id)
-    sql = """
+    clause = (" WHERE " + " AND ".join(where)) if where else ""
+    return clause, params
+
+
+def count_trades(
+    conn: sqlite3.Connection,
+    account_id: Optional[int] = None,
+    machine_id: Optional[int] = None,
+) -> int:
+    clause, params = _trades_where(account_id, machine_id)
+    sql = f"SELECT COUNT(*) AS c FROM trades t{clause}"
+    row = conn.execute(sql, tuple(params)).fetchone()
+    return int(row["c"] if row else 0)
+
+
+def list_trades(
+    conn: sqlite3.Connection,
+    limit: int = 200,
+    account_id: Optional[int] = None,
+    machine_id: Optional[int] = None,
+    offset: int = 0,
+) -> list[dict]:
+    clause, params = _trades_where(account_id, machine_id)
+    sql = f"""
         SELECT t.*, a.name AS account_name, m.name AS machine_name
         FROM trades t
         LEFT JOIN accounts a ON a.id = t.account_id
         LEFT JOIN machines m ON m.id = t.machine_id
+        {clause}
+        ORDER BY COALESCE(t.close_time, t.open_time, t.created_at) DESC
+        LIMIT ? OFFSET ?
     """
-    if where:
-        sql += " WHERE " + " AND ".join(where)
-    sql += " ORDER BY COALESCE(t.close_time, t.open_time, t.created_at) DESC LIMIT ?"
-    params.append(limit)
+    params.extend([limit, max(0, int(offset))])
     cur = conn.execute(sql, tuple(params))
     rows = []
     for r in cur.fetchall():