feat: 🎸 posthog (#1945)

added reverse proxy

# Description

Please include a summary of the changes and the related issue. Please
also include relevant motivation and context.

## Checklist before requesting a review

Please delete options that are not relevant.

- [ ] My code follows the style guidelines of this project
- [ ] I have performed a self-review of my code
- [ ] I have commented hard-to-understand areas
- [ ] I have ideally added tests that prove my fix is effective or that
my feature works
- [ ] New and existing unit tests pass locally with my changes
- [ ] Any dependent changes have been merged

## Screenshots (if appropriate):

frontend/app/App.tsx

@@ -22,7 +22,9 @@ if (
   process.env.NEXT_PUBLIC_POSTHOG_HOST != null
 ) {
   posthog.init(process.env.NEXT_PUBLIC_POSTHOG_KEY, {
-    api_host: process.env.NEXT_PUBLIC_POSTHOG_HOST,
+    ui_host: process.env.NEXT_PUBLIC_POSTHOG_HOST,
+    // eslint-disable-next-line @typescript-eslint/restrict-template-expressions
+    api_host: `${process.env.NEXT_PUBLIC_FRONTEND_URL}/ingest`,
     opt_in_site_apps: true,
     disable_session_recording: true,
   });

vercel.json

@@ -3,5 +3,11 @@
         "deploymentEnabled": {
             "main": false
         }
-    }
+    },
+    "rewrites": [
+        {
+            "source": "/ingest/:path*",
+            "destination": "https://app.posthog.com/:path*"
+        }
+    ]
 }