refactor: quality-of-life improvements — test coverage, type safety, reduce duplication

[devin-ai-integration]

Summary

Three targeted quality improvements, no functional changes:

1. reports.js test coverage: 64% → 94% — Added 7 tests covering the PDF generation success path (content rendering, empty entries, page overflow at y>700, separator lines every 5 entries, null descriptions) and CSV writer verification (correct entries passed to writeRecords, header/filename configuration). Remaining uncovered lines (127-134) are the res.download callback which requires a real filesystem file. Test helpers (setupClientAndEntries, setupPdfMock, requestPdfAndGetMock) reduce mock duplication.

2. DashboardPage @ts-expect-error removal — Migrated 3 Grid usages from deprecated v1 item xs={12} prop syntax to v2 size={{ xs: 12 }} API, consistent with how ReportsPage already uses Grid.

3. Shared getApiErrorMessage utility — Extracted the repeated error extraction pattern:

   // Before (repeated 8× across 3 pages):
   const error = err as { response?: { data?: { error?: string } } };
   setError(error.response?.data?.error || 'Failed to ...');
   
   // After:
   setError(getApiErrorMessage(err, 'Failed to ...'));

Link to Devin session: https://partner-workshops.devinenterprise.com/sessions/3ebb41e8a4f44659b6d75522cc44b0c6

[devin-ai-integration]

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[sonarqubecloud]

Quality Gate passed

Issues
4 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
1.3% Duplication on New Code

See analysis details on SonarQube Cloud