Configure Sentry to only send traces from select deployments (#3077)

Sentry has been gathering statistics from our preview environment. This
skews the performance metrics. This PR makes it so that it only gathers
statistics from prod.

<img width="2672" alt="image"
src="https://github.com/user-attachments/assets/b8a9fd87-9faf-457b-b78b-6741e11154e1">


https://watonomous.sentry.io/performance/trace/4bf52500e7c94bb1821bb275d8cd2e26/?environment=production&fov=0,4399.89990234375&node=txn-49f3b18bc3b14ba59da3471900a05c72&project=4506137389105152&source=web_vitals_module&statsPeriod=7d&timestamp=1725305801&transaction=/

sentry.client.config.ts

@@ -5,23 +5,42 @@
 import * as Sentry from "@sentry/nextjs";
 import { websiteConfig } from '@/lib/data'
 
+// proportion of traces to send to Sentry
+const TRACES_SAMPLE_RATE = 1.0
+
 if (process.env.NODE_ENV === 'production') {
   Sentry.init({
     dsn: websiteConfig.sentry_dsn,
 
-    // Adjust this value in production, or use tracesSampler for greater control
-    tracesSampleRate: 1,
+    tracesSampler({ location }) {
+      // Not sure what traces don't have a location, but sample them just in case.
+      if (!location) {
+        return TRACES_SAMPLE_RATE;
+      }
+
+      // Only send traces to Sentry if the user is on the production domain
+      if (!location.host.endsWith('watonomous.ca')) {
+        return 0.0
+      }
+
+      // Do not send traces to Sentry if the user is in the preview environment
+      if (location.host === 'rgw-preview.watonomous.ca') {
+        return 0.0
+      }
+
+      return TRACES_SAMPLE_RATE;
+    },
 
     // Setting this option to true will print useful information to the console while you're setting up Sentry.
     debug: false,
 
-    // TODO: reduce session sample rate in production
+    // TODO: reduce session sample rate in production if needed
     replaysSessionSampleRate: 1.0,
     replaysOnErrorSampleRate: 1.0,
 
     tunnel: websiteConfig.sentry_tunnel,
 
-    integrations: []
+    integrations: [],
   });
 
   // Lazy-load the Sentry Replay integration