init: update the default sample Score file generated

[Abhishek9639]

Description

The default score.yaml generated by score-compose init used a basic nginx example that didn't really show what Score is capable of. This PR replaces it with a more meaningful sample that demonstrates resource provisioning, environment variable substitution, and routing things that actually help a new user understand why Score is useful.

What does this PR do?

Closes #475

Updates DefaultScoreFileContent in internal/command/init.go to generate a richer sample score.yaml that:

• Uses scorespec/sample-score-app:latest instead of nginx
• Provisions a postgres database resource and injects its connection details as environment variables (DB_HOST, DB_PORT, DB_DATABASE, etc.)
• Provisions a dns resource and a route resource for HTTP routing
• Points to the Getting Started guide: https://docs.score.dev/docs/get-started/

All three resource types (postgres, dns, route) are included in the default provisioners, so score-compose generate works out of the box with no extra setup needed.

Also updated TestInitNominal and TestInitAndGenerate_with_sample to reflect the new sample structure.

Types of changes

• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• My change requires a change to the documentation.
• I've signed off with an email address that matches the commit author.

[Abhishek9639]

Hi @mathieu-benoit,
I've raised a PR for this. Updated the default sample in init.go as suggested, and adjusted the related tests accordingly. All tests pass locally.
Please take a look when you get a chance, happy to make any changes.
Thanks

[mathieu-benoit]

Thanks! Small feedback to remove the empty lines in the Score file please.

[Abhishek9639]

Hi @mathieu-benoit,
Done, removed the empty lines from the Score file.
Thanks for the feedback.

[mathieu-benoit]

Quick question of my final review.

[mathieu-benoit]

LGTM

[Abhishek9639]

Hii @mathieu-benoit,
I have sent the draft of "Project Melody" to the link you shared. Please review it once. Also, could you let me know whether you are planning to apply for a CNCF project for Term 2 or not?
Thanks