feat: Add hello world workflow

[google-labs-jules]

This change introduces a new GitHub Actions workflow named 'hello_world_from_jules.yml'. The workflow is triggered on pull requests, has 'write-all' permissions, and runs a single job to print 'Hello World'.

Fixes #31

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PR created automatically by Jules for task 11556041722236705612 started by @schcamille

[google-labs-jules]

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