Add Deprecation/Sunset headers on /v1

[greatest0fallt1me]

Description

This is a backend issue for the GrantFox campaign. This is a backend issue for the GrantFox FWC26 campaign. Stamp headers on v1 endpoints.

Requirements and Context

• Implement per the description
• Add focused tests for the change
• Document any API/visible changes
• Adhere to repo's lint and code style
• Must be secure, tested, and documented
• Should be efficient and easy to review

Suggested Execution

1. Fork the repo and create a branch

   git checkout -b task/deprecation-headers

2. Implement changes
   • src/middleware/deprecation.ts (new)
3. Test and commit
   • Run the repo's standard test suite and lint
   • Cover edge cases; include output in the PR

Example commit message

feat: Deprecation/Sunset headers

Acceptance Criteria

• Implementation matches the description
• Tests added and passing
• Code review approved
• Docs updated

Guidelines

• Minimum 90% test coverage on changed lines
• Input validation at the boundary; standardized error envelope
• Structured logging with correlation IDs
• Clear documentation and inline comments
• Timeframe: 96 hours

[VictorEzenma]

@VictorEzenma has applied to work on this issue as part of the Stellar Wave Program's 7th wave.

Hello, I would like to contribute by applying the necessary fixes and improvements

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

[ValJnr-dev1]

@ValJnr-dev1 has applied to work on this issue as part of the Stellar Wave Program's 7th wave.

Hi Maintainer,

I’m a smart contract and full-stack developer and would love to contribute to this issue. I’m an experienced contributor with hands-on expertise in Rust, Soroban, Cairo, and TypeScript.

I’m passionate about building secure, scalable blockchain solutions, with a strong emphasis on writing clean and maintainable code. Based on the scope of this issue, I’m confident I can deliver a complete solution within 24 hours of assignment.

I’d greatly appreciate the opportunity to contribute and help move this forward.

ℹ️ Repo Maintainers: To accept this application, review their application or assign @ValJnr-dev1 to this issue.

[Gbotemi-ojo]

@Gbotemi-ojo has applied to work on this issue as part of the Stellar Wave Program's 7th wave.

I can work on this maintainer,assign this to me maintainer

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

[TemiMustapha]

@TemiMustapha has applied to work on this issue as part of the Stellar Wave Program's 7th wave.

i will like to work on this

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

[Theraxia]

@Theraxia has applied to work on this issue as part of the Stellar Wave Program's 7th wave.

hi maintainer, i would like to work on this issue, thanks

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

[drips-wave]

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

🧑‍💻 @VictorEzenma: 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

When opening a PR, please link it to this issue to ensure it gets tracked accurately. Points are awarded when this issue is marked as completed by the maintainer.

🤠 Repo maintainers: Please keep an eye on the contributor's progress and review their work before the due date. You can manage this issue, including adjusting its complexity and points, here.

🌊 Happy Wave 🌊