Refactor backend middleware stack for composability and testability

[Smartdevs17]

Description

Current middleware is monolithic with mixed concerns. Refactor into focused, composable middleware functions with proper error handling and comprehensive test coverage.

Acceptance Criteria

• Each middleware has single responsibility
• Error handling centralized in error middleware
• Request/response logging with structured format
• 90%+ test coverage for each middleware
• Performance benchmark before/after

Technical Scope

• backend/src/middleware/
• Edge: middleware ordering dependencies, request context propagation

[vstudio79]

@vstudio79 has applied to work on this issue as part of the Stellar Wave Program's 5th wave.

Hi can I be assigned to this issue?

ℹ️ Repo Maintainers: To accept this application, review their application or assign @vstudio79 to this issue.

[soomtochukwu]

@soomtochukwu has applied to work on this issue as part of the Stellar Wave Program's 5th wave.

Heyyy :) 👋🏿
Let me take this off your plate ASAP

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

[drips-wave]

Congratulations, @vstudio79! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on June 2, 2026.

🧑‍💻 @vstudio79: 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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