Build hn-reader: keyboard-driven Hacker News reader

Vite/React + shadcn/ui frontend with Superhuman-style keyboard nav
(j/k/o/v/e/s/u, feed switching, localStorage caching for instant
loads) backed by an Express API that polls the HN Firebase API into
Postgres and serves cached feeds/comments. Instrumented with
OpenTelemetry (traces/metrics/logs via OTLP/HTTP).

server/otel.js

@@ -0,0 +1,59 @@
+// OpenTelemetry bootstrap: sends traces, metrics and logs to the LGTM
+// stack's OTLP/HTTP collector at http://localhost:4318. Must be required
+// before any other module so auto-instrumentation can patch http/express/pg.
+const { NodeSDK } = require('@opentelemetry/sdk-node')
+const { getNodeAutoInstrumentations } = require('@opentelemetry/auto-instrumentations-node')
+const { OTLPTraceExporter } = require('@opentelemetry/exporter-trace-otlp-http')
+const { OTLPMetricExporter } = require('@opentelemetry/exporter-metrics-otlp-http')
+const { OTLPLogExporter } = require('@opentelemetry/exporter-logs-otlp-http')
+const { PeriodicExportingMetricReader } = require('@opentelemetry/sdk-metrics')
+const { BatchLogRecordProcessor } = require('@opentelemetry/sdk-logs')
+const { resourceFromAttributes } = require('@opentelemetry/resources')
+const { ATTR_SERVICE_NAME, ATTR_SERVICE_VERSION } = require('@opentelemetry/semantic-conventions')
+const { logs } = require('@opentelemetry/api-logs')
+
+const endpoint = process.env.OTEL_EXPORTER_OTLP_ENDPOINT || 'http://localhost:4318'
+
+const resource = resourceFromAttributes({
+  [ATTR_SERVICE_NAME]: 'hn-reader-api',
+  [ATTR_SERVICE_VERSION]: '1.0.0',
+})
+
+const sdk = new NodeSDK({
+  resource,
+  traceExporter: new OTLPTraceExporter({ url: `${endpoint}/v1/traces` }),
+  metricReader: new PeriodicExportingMetricReader({
+    exporter: new OTLPMetricExporter({ url: `${endpoint}/v1/metrics` }),
+    exportIntervalMillis: 15000,
+  }),
+  logRecordProcessors: [
+    new BatchLogRecordProcessor(new OTLPLogExporter({ url: `${endpoint}/v1/logs` })),
+  ],
+  instrumentations: [
+    getNodeAutoInstrumentations({
+      '@opentelemetry/instrumentation-fs': { enabled: false },
+    }),
+  ],
+})
+
+sdk.start()
+
+process.on('SIGTERM', () => sdk.shutdown().finally(() => process.exit(0)))
+
+const otelLogger = logs.getLogger('hn-reader-api')
+
+// Small structured logger: prints to stdout (captured by journald) and
+// emits an OTLP log record so logs show up alongside traces in Grafana.
+function log(severity, message, attributes = {}) {
+  const line = `[${severity}] ${message} ${Object.keys(attributes).length ? JSON.stringify(attributes) : ''}`
+  if (severity === 'ERROR') console.error(line)
+  else console.log(line)
+
+  otelLogger.emit({
+    severityText: severity,
+    body: message,
+    attributes,
+  })
+}
+
+module.exports = { log }