feat: Gtfs change tracker 1634

[jcpitre]

closes #1634

This pull request introduces a new GTFS change tracking feature to the pipeline. It adds a new Cloud Function (gtfs-change-tracker) that computes and stores structured diffs between pairs of GTFS datasets, integrates this function into the batch processing workflow, and updates the infrastructure to support the new service. The changes span Python code, requirements, and Terraform infrastructure.

GTFS Change Tracking Feature:

• Added a new Cloud Function gtfs-change-tracker that computes diffs between two GTFS datasets, uploads the changelog to GCS, and persists a summary in the database. This includes the main logic (src/main.py), configuration (function_config.json), and dependencies (requirements.txt, requirements_dev.txt). [1] [2] [3] [4]

• Implemented a utility function create_http_gtfs_change_tracker_task to enqueue Cloud Tasks for the new function, and integrated it into the pipeline so that a change tracking task is created when a new dataset is processed and a previous dataset exists. [1] [2] [3]

Infrastructure and Deployment:

• Updated Terraform to provision the new Cloud Function, deploy its code, create a dedicated Cloud Tasks queue, and set up required IAM permissions. This ensures the function is properly deployed and can be invoked by the batch processor. [1] [2] [3] [4] [5] [6] [7]Summary:

Testing

Testing was done with only 1 datasset. Here is the curl call used:

 curl -X POST "https://northamerica-northeast1-mobility-feeds-dev.cloudfunctions.net/gtfs-change-tracker-dev" \ 
   -H "Authorization: bearer $(gcloud auth print-identity-token)" \
   -H "Content-Type: application/json" \
   -d '{
     "feed_stable_id": "ntd-90200",
     "base_dataset_stable_id": "ntd-90200-202604081703",
     "new_dataset_stable_id": "ntd-90200-202605211420"
}'

The resulting json diff report is:
ntd-90200-202605211420_ntd-90200-202604081703_changelog.json

Please make sure these boxes are checked before submitting your pull request - thanks!

• Run the unit tests with ./scripts/api-tests.sh to make sure you didn't break anything
• Add or update any needed documentation to the repo
• Format the title like "feat: [new feature short description]". Title must follow the Conventional Commit Specification(https://www.conventionalcommits.org/en/v1.0.0/).
• Linked all relevant issues
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[davidgamez]

🥇