feat(docs): add Sentry SDK for error tracking, replay, and metrics (#122)

## Summary

Adds @sentry/astro to the docs website for monitoring errors, user
sessions, and performance. Also tracks custom metrics when users
interact with the hero install command section.

## Changes

- Integrates `@sentry/astro` with client and server configs
- Enables error tracking, session replay (10% sample, 100% on error),
and tracing
- Adds two custom metrics:
  - `hero_command_copied` - tracks when users copy an install command
- `hero_install_method_selected` - tracks when users switch between
curl/npx/npm/pnpm/bun

## Test Plan

1. Run `cd docs && bun run dev`
2. Open browser console and verify Sentry initializes (enable `debug:
true` in client config if needed)
3. Click the dropdown to change install method → metric sent
4. Click copy button → metric sent
5. Check Sentry project **Insights > Metrics** for the custom metrics

## Notes

- `SENTRY_AUTH_TOKEN` env var needed for source maps upload in
production
- SDK is enabled in all environments including dev for testing

---
Closes #117

---------

Co-authored-by: Claude Opus 4.5 <noreply@anthropic.com>

Author: betegon

docs/astro.config.mjs

@@ -1,4 +1,5 @@
 import starlight from "@astrojs/starlight";
+import sentry from "@sentry/astro";
 import { defineConfig } from "astro/config";
 
 // Allow base path override via environment variable for PR previews
@@ -8,6 +9,14 @@ export default defineConfig({
   site: "https://cli.sentry.dev",
   base,
   integrations: [
+    sentry({
+      project: "cli-website",
+      org: "sentry",
+      authToken: process.env.SENTRY_AUTH_TOKEN,
+      sourceMapsUploadOptions: {
+        enabled: !!process.env.SENTRY_AUTH_TOKEN,
+      },
+    }),
     starlight({
       title: "Sentry CLI",
       favicon: "/favicon.png",

docs/bun.lock

@@ -9,6 +9,7 @@
   },
   "dependencies": {
     "@astrojs/starlight": "^0.31.1",
+    "@sentry/astro": "^10.38.0",
     "astro": "^5.1.1",
     "sharp": "^0.33.5",
     "shiki": "^3.21.0"

docs/package.json

@@ -0,0 +1,21 @@
+import * as Sentry from "@sentry/astro";
+
+Sentry.init({
+  dsn: "https://2aca5fe97c71868bc3aa7fb48620dc39@o1.ingest.us.sentry.io/4510798755856384",
+  sendDefaultPii: true,
+  integrations: [
+    Sentry.browserTracingIntegration(),
+    Sentry.replayIntegration(),
+  ],
+  enableLogs: true,
+  tracesSampleRate: 1.0,
+  replaysSessionSampleRate: 0.1,
+  replaysOnErrorSampleRate: 1.0,
+  // Enable in all environments (including development)
+  enabled: true,
+  // Uncomment to debug Sentry initialization
+  // debug: true,
+});
+
+// Expose globally for inline scripts
+window.Sentry = Sentry;

docs/sentry.client.config.js

@@ -0,0 +1,10 @@
+import * as Sentry from "@sentry/astro";
+
+Sentry.init({
+  dsn: "https://2aca5fe97c71868bc3aa7fb48620dc39@o1.ingest.us.sentry.io/4510798755856384",
+  sendDefaultPii: true,
+  enableLogs: true,
+  tracesSampleRate: 1.0,
+  // Enable in all environments (including development)
+  enabled: true,
+});

docs/sentry.server.config.js

@@ -329,7 +329,18 @@ const defaultOption = highlightedOptions[defaultIndex];
           });
           option.classList.add('selected');
           option.setAttribute('aria-selected', 'true');
-          
+
+          // Track install method selection with Sentry metrics
+          try {
+            if (typeof Sentry !== 'undefined' && Sentry.metrics && newLabel) {
+              Sentry.metrics.count('hero_install_method_selected', 1, {
+                attributes: { install_method: newLabel },
+              });
+            }
+          } catch (e) {
+            // Sentry not available, ignore
+          }
+
           // Close dropdown and return focus
           installBox.classList.remove('open');
           trigger.setAttribute('aria-expanded', 'false');
@@ -461,6 +472,18 @@ const defaultOption = highlightedOptions[defaultIndex];
               await navigator.clipboard.writeText(command);
               copyBtn.classList.add('copied');
               setTimeout(function() { copyBtn.classList.remove('copied'); }, 2000);
+
+              // Track copy event with Sentry metrics
+              try {
+                if (typeof Sentry !== 'undefined' && Sentry.metrics) {
+                  const installMethod = label ? label.textContent : 'unknown';
+                  Sentry.metrics.count('hero_command_copied', 1, {
+                    attributes: { install_method: installMethod },
+                  });
+                }
+              } catch (e) {
+                // Sentry not available, ignore
+              }
             }
           });
         }