Add structured log for client-side JavaScript errors via window.onerror handler

[Chucks1093]

Summary

Unhandled JavaScript errors that occur outside of React's render cycle (e.g. in event handlers, async callbacks, or third-party scripts) are never captured in structured logs. A window.onerror handler should capture these and emit a structured log before they disappear silently.

Scope

• Register a window.onerror handler on app initialisation
• Emit a debug-level structured log on each unhandled error with fields: message, source, line, col, error_type
• Handler should not suppress the default browser error behaviour (return false)
• Handler should be registered once and not re-registered on re-renders

Acceptance Criteria

• Handler registered once on app init, not on re-render
• Structured log emitted for each unhandled error with all five fields
• Default browser error behaviour preserved
• Handler does not catch errors already caught by the React error boundary

ETA: 12 hours

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Coordinate on Telegram

[CodeMayor]

@CodeMayor has applied to work on this issue as part of the Stellar Wave Program's 7th wave.

I'd like to work on this issue because improving client-side error observability will make debugging production issues much easier without affecting application behaviour. I'll implement a single global window.onerror handler during app initialization, emit structured debug logs with the required fields, preserve the browser's default error handling by returning false, ensure the handler is only registered once, and add focused tests covering registration and logging behaviour.

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[raymondidahor-bot]

@raymondidahor-bot has applied to work on this issue as part of the Stellar Wave Program's 7th wave.

I would love to work on this project. I can deliver within a short time. Please oblige me

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[wandooadzer-cmyk]

@wandooadzer-cmyk has applied to work on this issue as part of the Stellar Wave Program's 7th wave.

Can I work on this task?

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