Add Sentry, Pino logs, and OTel spans on WS pipeline (M2).

Capture REST/WS/SSE errors in Sentry, emit structured pino logs with correlation IDs, and trace the book-tick pipeline to Sentry via OpenTelemetry.

Co-authored-by: Cursor <cursoragent@cursor.com>

src/instrumentation/sentry.ts

@@ -0,0 +1,26 @@
+import * as Sentry from "@sentry/node";
+
+const dsn = process.env.SENTRY_DSN?.trim();
+
+export function initSentry(): void {
+  if (!dsn) return;
+
+  Sentry.init({
+    dsn,
+    environment: process.env.NODE_ENV ?? "development",
+    tracesSampleRate: process.env.NODE_ENV === "production" ? 0.1 : 1,
+    integrations: [Sentry.httpIntegration(), Sentry.expressIntegration()],
+  });
+
+  process.on("unhandledRejection", (reason) => {
+    Sentry.captureException(
+      reason instanceof Error ? reason : new Error(String(reason)),
+    );
+  });
+
+  process.on("uncaughtException", (error) => {
+    Sentry.captureException(error);
+  });
+}
+
+export { Sentry };