Add timeout and circuit breaker for external API calls

[Smartdevs17]

Description

External API calls (Stellar, Stripe, KYC providers) have no timeouts causing cascading failures. Implement configurable timeouts and circuit breakers.

Acceptance Criteria

• Configurable timeout per external service
• Circuit breaker with failure threshold and recovery timeout
• Fallback responses for degraded functionality
• Timeout and circuit breaker metrics
• Graceful degradation when circuit is open
• Manual circuit reset for emergency recovery

Technical Scope

• backend/src/middleware/circuit-breaker.ts
• backend/src/services/stellar.ts
• backend/src/services/stripe.ts
• Edge: partial response handling, timeout vs cancellation semantics

[abdulqoyumadegoke]

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

I would like to work on this task

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[Nabeelahh]

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

Hi maintainer I have thoroughly read the description to this issue and I can resolve this according to the description required ensuring it meet all the acceptance criteria kindly assign.

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[Sh4vii]

@Sh4vii has applied to work on this issue as part of the Stellar Wave Program's 5th wave.

Hello Ill like to work on this issue

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[OlaBakare]

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

Hi, I'd love to work on this issue. I can handle this issue.
Thank you.

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[Clinton6801]

@Clinton6801 has applied to work on this issue as part of the Stellar Wave Program's 5th wave.

I believe I'm experienced enough to solve this issue

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[dee-john]

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

Hi, I'd like to work on this issue! because I am very conversant with solving problems like this!

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[iBotayo]

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

I’d like to work on this issue because it improves system resilience and fault isolation in critical external integrations, which is essential for maintaining stability in payment and identity workflows.

I have experience building backend services in Node.js/TypeScript where I’ve implemented request timeouts, retry strategies, and failure handling for external APIs. I’m comfortable designing circuit breaker patterns with configurable thresholds, adding graceful degradation paths, exposing metrics for observability, and ensuring safe cancellation semantics to prevent cascading failures across dependent services.

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[numdinkushi]

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

Hi, I would like to work on this issue. Please assign to me

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[DeborahOlaboye]

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

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

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