Show error if contract method has invalid data structure

[tom2drum]

Description and Related Issue(s)

When a contract method has an invalid data structure (e.g., no outputs property), we display an alert within its accordion section instead of a generic 500 error for the entire page.

Also, it fixes the issue with an invalid address error when reading a contract method.

Checklist for PR author

• I have tested these changes locally.
• I added tests to cover any new functionality, following this guide
• Whenever I fix a bug, I include a regression test to ensure that the bug does not reappear silently.
• If I have added, changed, renamed, or removed an environment variable, I have updated the list of environment variables in the documentation and made the necessary changes to the validator script according to the guide