[Aliussman]

Description

Adds a Reports tab for the periodic report API from fireform-core/fireform-backend#737 (POST /api/v1/reports/generate and GET /api/v1/reports/{report_id}).

• Request form: choose Monthly / Quarterly / Annual, then the year and the month or quarter, and PDF or JSON output. Months and quarters that haven't started yet are disabled, matching the backend's FUTURE_PERIOD rule. The backend's error still shows if one comes back.
• Background generation: after the 202, the tab polls GET /reports/{report_id}, waiting the retry_after_seconds the API returns each time. It shows elapsed time and the next check. Polling stops after 10 minutes with a "check the worker" message.
• Switching tabs: the in-progress report is kept in memory in the zustand store (not localStorage), so you can leave Reports and come back without losing the job.
• PDF: a Download PDF button that saves through Electron's normal save dialog. No main-process changes.
• JSON: shown in the tab as summary cards, NERIS compliance, by-type and by-status bars, a per-period table and an incidents table, with a Download JSON button.
• Errors: 422 (validation and FUTURE_PERIOD), 503 QUEUE_UNAVAILABLE, 404 REPORT_NOT_FOUND, 500 REPORT_FAILED, PDF_NOT_FOUND, and an unreachable backend each get a clear message, with Check again / Start over where they make sense.

Files:

• src/renderer/lib/api.ts: typed generateReport / fetchReportResult, matching contracts/schemas/reporting.yaml, plus a ReportApiError that keeps error_code.
• src/renderer/features/reports/: Reports.tsx (UI) and hooks.ts (polling hook, plus period labels and file names that match the backend's).
• src/renderer/store/index.ts: activeReport state.
• src/renderer/App.tsx: nav item and route.

Notes for reviewers

• The UI offers PDF and JSON only. The backend also accepts format: "both", but GET /reports/{id} then returns only the JSON, so the PDF can't be downloaded. I can follow up on the backend if you'd like both.
• The backend's CORS setup doesn't expose Content-Disposition, so the renderer usually can't read the server's filename. The frontend names the file the same way the backend does (e.g. FireForm_Quarterly_2026-Q3.pdf).

Depends on fireform-core/fireform-backend#737.

Fixes #58

Type of change

• New feature (non-breaking change which adds functionality)

How Has This Been Tested?

• npm run typecheck: passes
• npm run lint: 0 errors. The 33 existing warnings are the same as on main; this PR adds none (eslint src/renderer/features/reports --max-warnings 0 passes).
• npm run build: passes
• Checked the real api.ts and hooks.ts code against a mock of the two endpoints (bundled with esbuild, run in Node). The mock answers 202 twice before the result. 26/26 checks passed:
  • PDF flow: two 202 responses honouring retry_after_seconds, then the PDF blob.
  • JSON flow: polling, then the PeriodicReport parsed correctly.
  • Request body: sends quarter or month only for the matching period type.
  • Errors surfaced with the right code and status: 422 FUTURE_PERIOD, 422 validation_errors, 503 QUEUE_UNAVAILABLE, 404 REPORT_NOT_FOUND, 500 REPORT_FAILED.
  • Period labels, file names and future-period checks.
• Not yet clicked through in the running app against the full backend stack (Postgres + Redis + Celery). To try it: run the backend from FireForm#737 with docker compose, run npm run dev, open Reports, and generate a PDF report and a JSON report.

Test Configuration:

• Node version: 24.12.0
• Docker/Compose version: N/A (mock backend)
• OS: Ubuntu Linux (x86_64)

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works (the repo has no frontend test runner; see the mock check above)
• New and existing unit tests pass locally with my changes
• Any dependent changes have been merged and published in downstream modules (needs feat: implement periodic report generation API (#557) fireform-backend#737)