Split API routes by domain with versioned namespacing

[Smartdevs17]

Description

All API routes are in flat files. Refactor to versioned domain grouping for better organization and versioning strategy.

Acceptance Criteria

• Versioned route prefixes (/v1/lending, /v1/oracle, /v1/governance)
• Domain-based route file organization
• Version migration middleware
• Deprecation headers for old versions
• OpenAPI spec per version
• No breaking changes to existing clients

Technical Scope

• api/src/routes/
• api/src/app.ts
• Edge: route conflict resolution, middleware duplication per version

[smog123]

@smog123 has applied to work on this issue as part of the Stellar Wave Program's 5th wave.

Please can you assign this issue to me ?

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[MorsH14]

@MorsH14 has applied to work on this issue as part of the Stellar Wave Program's 5th wave.

I know more about API route

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[Tundeakinbami-dev]

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

i can work on this issue

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[drips-wave]

Congratulations, @smog123! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on June 2, 2026.

🧑‍💻 @smog123: 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.

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