[Ganeshkumar Ashokavardhanan (ganeshkumarashok)]

Summary

Align the two remaining nonconforming public Timestamp field names with the
API's AIP naming conventions:

• MintActorJwtResponse.expires_at becomes expire_time.
• GoldenSnapshotStatus.take_golden_snapshot_at becomes snapshot_time.

Update in-repository callers and existing tests, regenerate protobuf and
declarative validation code, and document the _time naming rule. Retain the
existing validation, lifecycle, and JWT functional coverage; the additional
protobuf serialization test file has been removed.

Fixes #2415.

Breaking change

Regenerate clients and update references to these fields:

Before	After
expires_at / expiresAt	expire_time / expireTime
take_golden_snapshot_at / takeGoldenSnapshotAt	snapshot_time / snapshotTime
Go ExpiresAt / GetExpiresAt()	ExpireTime / GetExpireTime()
Go TakeGoldenSnapshotAt / GetTakeGoldenSnapshotAt()	SnapshotTime / GetSnapshotTime()

Timestamp semantics, types, and protobuf field numbers are unchanged. Old-name
aliases are not retained, following the project's pre-1.0 compatibility policy.
Please apply the breaking-change label.

Verification

• Race-enabled tests for the retained validation, lifecycle, and egress JWT packages; the public protobuf package builds.
• TestMintActorJWT through the functional API harness.
• Repository Linux-aware Go lint.
• Validation coverage check.
• hack/verify-all.sh: all 15 current repository verifiers passed on the latest conflict refresh.
• Full Linux/root/infrastructure test matrix (not run locally).

CI follow-up

The October 12 E2E failure was two timeouts to public httpbin.org in the
credential-injection suite. Current main includes #2535, which replaces that
external origin with an in-cluster echo server and restores the test after the
earlier upstream quarantine. This PR adds no test skip of its own.

Contribution note

This is a first contribution, opened as a draft for coordination and feedback.
GitHub Copilot CLI was used to help prepare the code, tests, and PR description.

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[Julian Gutierrez Oschmann (juli4n)]

Thanks for the first contribution! It looks like you need to to sign a Contributor License Agreement. Please also rebase on main and fix conflicts.

[Ganeshkumar Ashokavardhanan (ganeshkumarashok)]

Thanks for the first contribution! It looks like you need to to sign a Contributor License Agreement. Please also rebase on main and fix conflicts.

Thanks Julian Gutierrez Oschmann (@juli4n). Signed the CLA, rebased and fixed conflicts.