Add more design patterns for Go

[whotterre]

The repository currently offers a great collection of design patterns, but the Golang section could be expanded with more low-level design patterns. Enhancing this section would help developers structure scalable and maintainable Go applications while following best practices.

I propose implementing Go equivalents of the patterns available in the Java section, ensuring they are idiomatic and accompanied by real-world use case examples. This will provide developers with practical insights into applying these patterns in Go projects.

I'm happy to contribute by implementing these patterns and submitting pull requests. Let me know if this aligns with the repository's goals! 🚀