WPB-20208 Audit log on asset download

[battermann]

https://wearezeta.atlassian.net/browse/WPB-20208

Checklist

• Add a new entry in an appropriate subdirectory of changelog.d
• Read and follow the PR guidelines

[Copilot]

Pull Request Overview

This PR implements comprehensive audit logging for asset operations in the Cargohold service, extending beyond upload events to include download, signed URL creation, and remote asset download logging.

Key changes include:

• Enhanced audit logging functions to cover download, signed URL creation, and remote asset operations
• Updated asset handling functions to include audit metadata and qualified principals for proper logging
• Comprehensive unit tests with property-based testing to validate audit log JSON structure
• Integration tests covering various federated download scenarios across multiple backends

Reviewed Changes

Copilot reviewed 21 out of 21 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
services/cargohold/src/CargoHold/API/AuditLog.hs	Expanded audit logging with new functions for download, URL creation, and remote access
services/cargohold/src/CargoHold/API/V3.hs	Updated asset operations to support qualified principals and audit metadata
services/cargohold/src/CargoHold/Util.hs	Modified signed URL generation to include audit logging
services/cargohold/src/CargoHold/S3.hs	Added Arbitrary instances and cleaned up type signatures
services/cargohold/test/unit/Test/CargoHold/API/AuditLogTest.hs	Property-based tests for audit log JSON validation
services/cargohold/test/unit/Test/CargoHold/API/LogJSON.hs	Test utilities for structured JSON logging
integration/test/Test/Cargohold/API.hs	Enhanced integration tests for federated audit logging scenarios

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[blackheaven]

they don't seems to be used, maybe we can rely on lens-aeson instead.

[battermann]

Thanks, I'll remove these in the follow-up PR to reduce the number of rebases...

[pcapriotti]

LGTM