"timeframe" on portfolio history is now an enum

The timeframe query parameter on the portfolio history endpoints is now documented as an enum via the new PortfolioHistoryTimeframe schema, replacing the free-form string.

• Accepted values: 1Min, 5Min, 15Min, 1H, 1D.
• The API already rejected any other value, so request and response behavior is unchanged; only generated clients and validation tooling see the tighter type.

Broker API

• GET /v1/trading/accounts/{account_id}/account/portfolio/history

Trading API

• GET /v2/account/portfolio/history