Implement frontend mock data layer and service adapters

[Abidoyesimze]

Epic

Integration

Description

• Create typed mock service layer for auth, portfolio, strategy, and tx flows
• Centralize error handling and simulated latency/failure cases
• Provide a clear adapter pattern for future backend integration

Acceptance criteria

• Typed mock service utilities in place
• Shared error model across pages
• Simulated retry/failure flows implemented
• Adapter contract documented for future backend integration

Suggested GitHub labels

frontend, mock-data, architecture, priority-high

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[Menjay7]

Hi! I came across this issue and would love to work on it. I have experience with similar tasks and I'm confident I can investigate, implement a clean solution, and thoroughly test it before submitting a PR. If the issue is still open, I would appreciate it if you could assign it to me. Thank you!

[OluwapelumiElisha]

Hello,

I would like to work on this issue.

[johnsmccain]

@johnsmccain has applied to work on this issue as part of the Stellar Wave Program's 6th wave.

I’d like to contribute to #474 by implementing a strongly typed mock service layer with reusable adapters, centralized error handling, and realistic latency/retry/failure simulations to ensure a smooth transition to backend integration while maintaining a clean and scalable frontend architecture.

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

[drips-wave]

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

🧑‍💻 @johnsmccain: 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

When opening a PR, please link it to this issue to ensure it gets tracked accurately. Points are awarded when this issue is marked as completed by the maintainer.

🤠 Repo maintainers: Please keep an eye on the contributor's progress and review their work before the due date. You can manage this issue, including adjusting its complexity and points, here.

🌊 Happy Wave 🌊

[grantfox-oss]

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

Next steps:

1. Open a Pull Request referencing this issue (e.g., Closes #474)
2. Your PR will be reviewed by the Neurowealth maintainers

Good luck! Track your progress on GrantFox.

[grantfox-oss]

🎉 This issue has been marked as completed on GrantFox as part of the Official Campaign campaign!

@johnsmccain's PR #483 was approved and merged by @robertocarlous.

🏆 @johnsmccain: You earned 35 FoxPoints for this contribution! Your current tier: Explorer (48 total points). Track your full progress on GrantFox.

👏 Great work, @johnsmccain! Keep contributing to Neurowealth.