The server listens on http://localhost:8080 (override with `PORT`). Templates, static assets, and sample data are read from disk on every request — edit a file and refresh the browser; no restart needed.
Everything — pages, static assets, and the API — sits behind Google sign-in restricted to the school's Google Workspace domain. Unauthenticated requests get the login page (API paths get a 401). The OAuth 2.0 Web application client (authorized JavaScript origins must include `http://localhost:8080` for local development) is read from `creds/oauth-client.json` — the JSON downloaded from the Cloud console — or from `GOOGLE_CLIENT_ID` when set; the server refuses to start with neither. After Google sign-in the server issues its own HMAC-signed session cookie; set `SESSION_KEY` to keep sessions valid across restarts and instances (without it each start generates a random key).
To capture authenticated pages with the screenshot tooling, launch the capture browser (`go run ./tools/capturebrowser`), sign in to the local server there once, and use `tools/browse` or `tools/screenshot -remote` — the session cookie lives in the capture profile. Plain `tools/screenshot` runs a fresh headless browser with no session and captures the login page.
The server reads local data from `sampledata/`, mirroring the production Sheets layout: one directory per app, one CSV file per table, first row is the schema. It goes through the same data-source interface production backends implement, so app code never knows which backend it is talking to.
switches the directory app to the Google Sheets source. At startup the directory tables are read from the spreadsheet and normalized into the in-memory data model (see `docs/data.md`); the server refuses to start if that load fails, and the model reloads every five minutes. Requires the service account key at `creds/service-account.json` (the directory is gitignored) with the Sheets API enabled and the spreadsheet shared read-only with the service account. Real data never leaves the process: nothing is written to disk.
