Chore: Publish frontend metrics from github actions (#110271)

* remove build size from ci scripts, test adding a github action step

* generate pa11y results file

* setup node

* don't need grabpl

* get key from vault

* doublequote env var

* write node script for publishing

* update CODEOWNERS

* add some logging

* yarn install...

* tidy up

* only on main branch

.github/workflows/scripts/publish-frontend-metrics.mts

@@ -0,0 +1,75 @@
+import fs from 'node:fs'
+
+interface Payload {
+  name: string;
+  value: number;
+  interval: number;
+  mtype: string;
+  time: number;
+}
+
+console.log("Publishing metrics");
+
+// Get API key from environment variable
+const key = process.env.GRAFANA_MISC_STATS_API_KEY;
+if (!key) {
+  throw new Error("API key is required. Provide it via the GRAFANA_MISC_STATS_API_KEY environment variable");
+}
+
+const unixTimestamp = Math.floor(Date.now() / 1000);
+const data: Payload[] = [];
+
+const input = fs.readFileSync(0, "utf-8");
+// parse metrics from input
+const regexp = /^Metrics: (\{.+\})/ms;
+const matches = input.match(regexp);
+
+if (!matches) {
+  throw new Error("No metrics found");
+}
+
+console.log('matches[0]', matches[0])
+console.log('matches[1]', matches[1])
+
+const metrics: Record<string, string> = JSON.parse(matches[1]);
+
+// Convert metrics to payload format
+for (const [metricName, valueStr] of Object.entries(metrics)) {
+  const value = parseInt(valueStr, 10);
+  if (isNaN(value)) {
+    throw new Error(`Metric "${metricName}" has invalid value format: "${valueStr}"`);
+  }
+
+  data.push({
+    name: metricName,
+    value: value,
+    interval: 60,
+    mtype: "gauge",
+    time: unixTimestamp,
+  });
+}
+
+const jsonPayload = JSON.stringify(data);
+console.log(`Publishing metrics to https://graphite-us-central1.grafana.net/metrics, JSON: ${jsonPayload}`);
+
+const url = 'https://graphite-us-central1.grafana.net/metrics';
+const username = '6371';
+const headers = new Headers();
+headers.set("Content-Type", "application/json");
+headers.set('Authorization', 'Basic ' + Buffer.from(username + ":" + key).toString('base64'));
+
+try {
+  const response = await fetch(url, {
+    method: "POST",
+    headers,
+    body: jsonPayload,
+  });
+
+  if (!response.ok) {
+    throw new Error(`Metrics publishing failed with status code ${response.status}`);
+  }
+
+  console.log("Metrics successfully published");
+} catch (error) {
+  throw new Error(`Metrics publishing failed: ${error instanceof Error ? error.message : String(error)}`);
+}