fix(cryptogen): improve error handling and add config parsing test

[sachin9058]

Type of change

• Improvement
• Test update

Description

This PR improves error handling in the cryptogen CLI and adds test coverage for configuration parsing failures.

Changes include:

• removing ignored errors from fmt.Print/Println calls
• improving error propagation with context in configuration parsing
• standardizing error output to stderr with proper exit codes
• adding a test to validate behavior on invalid configuration input

These changes improve reliability and make failures easier to diagnose without modifying core functionality.

[sachin9058]

Hi @mbrandenburger,

I’ve incorporated the suggested improvements and cleaned up the error handling and tests in this PR. Would appreciate your review when you get a chance.

Thanks!