Add ETag support for public GET endpoints

[EmmanuelOchaje]

Context

Clients re-download unchanged event lists.

Task

• Enable weak ETags and test 304 responses

Acceptance criteria

• Test asserts 304

This issue is self-contained and can be picked up independently of any other open issue.

[EurekaZainMalik]

@EurekaZainMalik has applied to work on this issue as part of the Stellar Wave Program's 9th wave.

Hi maintainer I would like to work on this issue please assign

ℹ️ Repo Maintainers: To accept this application, review their application or assign @EurekaZainMalik to this issue.

[Luna-netty]

@Luna-netty has applied to work on this issue as part of the Stellar Wave Program's 9th wave.

Hi maintainer, I'd like to work on this issue.

ℹ️ Repo Maintainers: To accept this application, review their application or assign @Luna-netty to this issue.

[devgrace100]

@devgrace100 has applied to work on this issue as part of the Stellar Wave Program's 9th wave.

Hi maintainer, I'd like to work on this issue.

ℹ️ Repo Maintainers: To accept this application, review their application or assign @devgrace100 to this issue.

[drips-wave]

Congratulations, @devgrace100! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on September 30, 2026.

🧑‍💻 @devgrace100: Please resolve the issue such that the repo's maintainers have enough time to review your contribution before the due date. You'll earn Points for completing the issue on-time, which will make you eligible for a share of the Stellar Wave Program's reward pool.

Warning

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