Add a new annotation to define a env-file for the run command per container

[fabiosammy]

✨ Summary

Added support for run environment file annotations in container mutation.

🔗 Resolves:

So, the idea behind this is to use a file that is already in the container, defining the list of environments instead of updating the k8s manifests every time a new environment is needed.

✅ Checklist

• 🖊️ Commits are signed
• 🧪 Tests added/updated: (See the Testing Guide for when to use each type and how to run them)
  • 🔹 Unit
  • 🔸 Integration
  • 🌐 E2E (Connect)
  • 🔑 E2E (Service Account)
• 📚 Docs updated (if behavior changed)

🕵️ Review Notes & ⚠️ Risks

This is my first time contributing to a "go" repository. I did it using the Claude AI, so sorry about that.
I feel that this should not be here, but a new environment should be available, something like OP_RUN_ENV_FILE, but I could not figure out which project I should contribute to.