Session 10: Internal auth refactor, prefetch cascade keys, Sentry, welcome email (1286 tests)

src/app.js

@@ -1,4 +1,10 @@
 require('dotenv').config();
+// Session 10 — Sentry must initialize BEFORE express is required so
+// the instrumentation hooks attach correctly. Graceful no-op when
+// SENTRY_DSN is unset.
+const { initSentry, Sentry } = require('./utils/sentry');
+initSentry();
+
 const express = require('express');
 const cors = require('cors');
 const oddsRoutes = require('./routes/odds');
@@ -132,4 +138,10 @@ app.use('/api/grading', express.json({ limit: '256kb' }), correctionRoutes);
 const widgetRoutes = require('./routes/widget');
 app.use('/api/widget', widgetRoutes);
 
+// Session 10 — Sentry's Express error handler catches uncaught
+// errors from every route mounted above. Must come AFTER routes but
+// BEFORE any final express error handler. The noop client makes this
+// a safe no-op when SENTRY_DSN is unset.
+Sentry.setupExpressErrorHandler(app);
+
 module.exports = app;