Resolves a partial street address into a list of full address candidates, optionally selecting a specific candidate by index and verifying it.

Basic usage — omit index: returns an array of CompletedAddressItem results for the given partialStreet.

With index — specify index to resolve a single candidate. Returns a single CompletedAddressItem.

With index + verify=true — additionally runs the selected address through the USPS/Canada Post verifier and returns a StandardVerifiedAddress.

• Uses 1 lookup per call (plus 1 more if geocoding a result).