[MEDIUM] Missing request timeout handling in frontend API calls

[kilodesodiq-arch]

Engineering Gap

Frontend API calls in verification-api.ts, verification-inbox-api.ts, and useCampaigns.ts use fetch without AbortController timeouts. Network requests hang indefinitely if backend is unresponsive.

Codebase Evidence

• app/frontend/src/lib/verification-api.ts line 15+: fetch calls without AbortController
• app/frontend/src/lib/verification-inbox-api.ts line 10+: Same pattern
• No timeout wrapper utility in app/frontend/src/lib/

Risk Profile

UI hangs on network failure. User experience degraded in poor connectivity.

Remediation Strategy

Add fetchWithTimeout utility wrapping AbortController. Apply to all API calls. Default timeout 30s.

Success Conditions

• fetchWithTimeout utility created
• All API calls use timeout wrapper
• Timeout errors handled with user feedback

Change Surface

Files: app/frontend/src/lib/, all API call sites

Security Review

No security impact.

Completion Checklist

• Implementation completed
• Peer reviewed
• Tests passing
• Ready for merge