[kris7011]

Stacked on #1. Review and merge #1 first. GitHub then retargets this PR to main.

Problem

• The React dashboard had no tests (about 2,100 lines with a lot of status and translation logic).
• Bug: coverage rate shown as "7857%". The API builds "Schedule coverage is {coverageRate}%." with the server's culture. translateRiskMessage then called .replace(".", ""), which removes the first period. On a Danish machine (78,57%.) that happens to be the final period. With an English or invariant culture, for example in the Docker image or on a typical Linux/cloud host, the decimal point is removed and the dashboard shows "Vagtplanens dækningsgrad er 7857%."
• API_BASE_URL = "http://localhost:5026" was duplicated in 9 API modules and could not be configured.

Solution

• Bug fix: strip only the sentence-ending period (/\.$/). It works for both 78,57% and 78.57%.
• src/api/config.ts: one API_BASE_URL, configurable via VITE_API_BASE_URL (with a new .env.example). The default is unchanged.
• Tests: Vitest 5 + React Testing Library + jsdom.
  • fetch is stubbed with fixtures captured from the real API after POST /api/demo/reset (src/test/fixtures/*.json). The coverage message uses invariant formatting (78.57%), as on CI.
  • App.test.tsx: overview rendering and Danish translations, error page with "Prøv igen", dashboard staying visible while refreshing after "Generér vagtplan", preference profiles reloaded after "Nulstil demo-data".
  • WeeklyScheduleTable.test.tsx: shifts per weekday and assigned names, 14/4/10 counts, weekend label, "Kun ubesatte" / "Kun tildelte" filters, week staying visible on refresh, error and retry.
• CI: the frontend job now runs npm test between lint and build.
• README: frontend tests, VITE_API_BASE_URL, frontend check commands.

Test results

npm test        → 2 files, 8 tests passed
npm run lint    → 0 problems
npm run build   → OK
dotnet test     → 59 passed (backend unchanged)

I checked that the tests are meaningful: run against the main versions of App.tsx and WeeklyScheduleTable.tsx, 4 of 8 fail (coverage translation, refresh flicker in two places, missing preference reload).

Limitations

• SimulationPanel and the unassigned-shift and employee detail panels are only covered indirectly. Simulation and the API layer get more coverage in the backend integration test PR.
• The underlying culture dependency is in the backend (ScheduleOverviewService formats with the current culture). Changing the message format would affect API consumers, so I left it as is and made the frontend robust instead.

🤖 Generated with Claude Code