security(frontend): normalize API errors before rendering stream mutations

[arisu6804]

Problem

Raw provider and API errors can leak details or cause the UI to treat a retryable failure as success.

Objective

Deliver a production-quality improvement to API adapters and mutation error surfaces that creates measurable value for correctness, security, reliability, performance, or maintainability.

Implementation scope

• Map errors to stable codes, retryability, correlation ID, and safe user messages; preserve diagnostic detail only in protected telemetry.

Acceptance criteria

• No raw secrets or provider payloads reach the UI; retry actions match error policy; unknown errors fail closed.

Required validation

• Fixture normalization, redaction, retryability, and malformed-error tests.
• Existing tests and CI remain passing.
• Add regression coverage for the original failure mode.
• Do not weaken, delete, or skip unrelated tests to obtain a green build.

PR quality bar

• Keep the PR focused and explain design tradeoffs, compatibility impact, and test evidence.
• Avoid typo-only, documentation-only, cosmetic-only, or unrelated refactor submissions.

Out of scope

• Broad rewrites not required by the acceptance criteria.
• Changes to unrelated services, contracts, or user flows.

[KehiOla]

Hi maintainer,

I'd like to contribute to this security issue. I have experience working with frontend API integrations and error handling, and I can implement a focused, production-quality fix that normalizes API errors before they reach the UI.

My approach will map provider errors to stable error codes, retryability, correlation IDs, and safe user-facing messages while preserving diagnostic details only for telemetry. I'll also add comprehensive tests for normalization, redaction, retryability, malformed errors, and regression coverage without affecting unrelated functionality.

I'm confident I can deliver a clean, well-tested PR that meets the acceptance criteria and maintains compatibility with the existing codebase.

[grantfox-oss]

🦊 GrantFox — @KehiOla has been assigned to this issue as part of the Third Campaign campaign!

Next steps:

1. Open a Pull Request referencing this issue (e.g., Closes #140)
2. Your PR will be reviewed by the StreamPay-Organization maintainers

Good luck! Track your progress on GrantFox.