Validate address format before running address checker

[Dianaaiym]

Currently, the Address Checker (Blacklist, Sanctions, Phishing) runs validation even if the entered address is clearly malformed or invalid. This leads to unnecessary checks and a confusing UX. We need to first validate the address format based on the selected blockchain, and only run the checks if the address is structurally valid.

[Dianaaiym]

Update UI behavior for invalid address input in two contexts:

Send Screen: Highlight the address field and disable the "Send" button without showing an error message "Invalid Address".

Settings → Address Checker: Highlight the address field and display an error message if the input is invalid.