Add a new credit budget to a contract.
walletMode: "credits"): use maxCredits.
For dollar-based wallets (walletMode: "dollars"): use maxCreditsCents.
Duplicate (eventPropertyKey, eventPropertyValue) pairs are rejected with 409 Conflict.
Scope: contracts:writeBearer authentication header of the form Bearer <token>, where <token> is your auth token.
The unique identifier of the contract (UUID)
Human-readable label (e.g., "Dove")
Event property key (e.g., "business_unit")
Event property value (e.g., "dove")
Optional meter ID to scope to a specific credit type
Spending cap in credit units (credit-based wallets)
Spending cap in cents (dollar-based wallets)
Budget created