Rebalancing weight "percent" is now documented as a decimal string

Broker API

The percent field on the rebalancing portfolio weight request schema is now documented as a decimal string (type: string, format: decimal, example "50"), matching qty and notional elsewhere in the Broker API.

• Applies to both cash and asset weights on create portfolio, update portfolio, and create run.
• Values must still be greater than zero, and the weights in a request must still total exactly 100.
• Response percent on portfolio weights is unchanged and still returned as a string.
• Create-run amount, drift-band percent, and other decimal fields are unchanged.

Clients generated from the spec will now send percent as a string; server behavior is unchanged.

Affected Endpoints

• POST /v1/rebalancing/portfolios
• PATCH /v1/rebalancing/portfolios/{portfolio_id}
• POST /v1/rebalancing/runs