Add creator route param validation middleware

[Chucks1093]

Summary

Add middleware for validating creator route params before handlers run.

Scope

• validate creator route param input early
• return a consistent error for invalid params
• keep the middleware reusable across creator routes

Acceptance Criteria

• invalid creator params are rejected before handler logic runs
• route handlers stay simpler after adoption
• middleware is reusable across multiple routes

Contributor note: comment on the issue first and reach out in Telegram for updates or coordination: https://t.me/accesslayerorg

[Kaycee276]

@Kaycee276 has applied to work on this issue as part of the Stellar Wave Program's 3rd wave.

I'd like to work on this issue because pushing validation upstream into middleware is the right architectural pattern — it keeps route handlers clean, enforces consistency across every creator route, and ensures invalid inputs never reach business logic. I have experience writing reusable validation middleware in Node.js backends, including early param rejection with structured, consistent error responses, which maps directly to all three acceptance criteria here.

ℹ️ Repo Maintainers: To accept this application, review their application or assign @Kaycee276 to this issue.

[Yunusabdul38]

@Yunusabdul38 has applied to work on this issue as part of the Stellar Wave Program's 3rd wave.

can i work on this

ℹ️ Repo Maintainers: To accept this application, review their application or assign @Yunusabdul38 to this issue.

[drips-wave]

Congratulations, @Kaycee276! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on March 30, 2026.

🧑‍💻 @Kaycee276: 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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