Integrate Zustand DevTools for state inspection in development

[Kingsman-99]

Overview

Debugging Zustand wallet and UI state currently requires console.log. Add Redux DevTools integration so developers can inspect, replay, and time-travel through state changes in the browser.

Acceptance Criteria

• zustand/middleware devtools middleware applied to all stores: wallet store, invoice store, UI store
• Store names set explicitly: "WalletStore", "InvoiceStore", "UIStore" — visible in the DevTools panel
• DevTools integration enabled only in process.env.NODE_ENV === 'development'
• Production build has zero DevTools overhead — middleware tree-shaken out
• Action names logged for each state update (use named set calls instead of anonymous)
• immer middleware added alongside devtools for ergonomic nested state updates
• All existing store tests updated to work with the new middleware stack
• CONTRIBUTING.md section added: "Debugging state with Redux DevTools"
• TypeScript types unchanged — no impact on store consumers

[Douglas4tech]

@Douglas4tech has applied to work on this issue as part of the Stellar Wave Program's 6th wave.

I’m a full-stack and smart contract developer with experience building responsive frontend interfaces, scalable backend systems, and secure blockchain applications

ℹ️ Repo Maintainers: To accept this application, review their application or assign @Douglas4tech to this issue.

[lonerthefirst3-sudo]

@lonerthefirst3-sudo has applied to work on this issue as part of the Stellar Wave Program's 6th wave.

i would love to work on this

ℹ️ Repo Maintainers: To accept this application, review their application or assign @lonerthefirst3-sudo to this issue.

[grantfox-oss]

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Next steps:

1. Open a Pull Request referencing this issue (e.g., Closes #366)
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[drips-wave]

Congratulations, @lonerthefirst3-sudo! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on June 30, 2026.

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