Registers an expected arrival before the money moves, and creates the PAY_IN transaction immediately at PENDING_FUNDS with settlement_status: FUNDS_EXPECTED. The transaction exists before the funds do.

What the intent means depends on the account it's against:

• On a PAYMENT-purpose account the intent is the locked order, and onUnder decides what happens if the payer sends less than expected.
• On a CONVERSION or BALANCE account it's an optional announcement.

The response carries an indicativeRate with binding: false. It's an indication, never a lock, and this endpoint accepts no quoteId.