[predictoor] Confusing Error Message When Code Signing Is Skipped on macOS

[trizin]

When trying to run a predictoor on macOS without completing the code signing step, the following error message is displayed

insufficient balance to pay fees

This message is confusing and does not clearly indicate that the issue is related to the code signing process.

Expected Behavior:

The error message should clearly indicate that the failure is due to an issue with code signing, rather than a balance problem.

Full error log: Error log

Background: #1517