fix(analytics): add posthog ingest proxy rewrites and document env vars

Author: waleedlatif1

apps/sim/.env.example

@@ -41,3 +41,8 @@ API_ENCRYPTION_KEY=your_api_encryption_key # Use `openssl rand -hex 32` to gener
 # Admin API (Optional - for self-hosted GitOps)
 # ADMIN_API_KEY=  # Use `openssl rand -hex 32` to generate. Enables admin API for workflow export/import.
                   # Usage: curl -H "x-admin-key: your_key" https://your-instance/api/v1/admin/workspaces
+
+# Product Analytics - PostHog (Optional)
+# NEXT_PUBLIC_POSTHOG_KEY=phc_...        # Your PostHog project API key (from posthog.com or self-hosted)
+# NEXT_PUBLIC_POSTHOG_ENABLED=true       # Set to true to enable analytics. Omit or set to false to disable entirely.
+                                          # When disabled: server SDK never initializes, client SDK never loads.

apps/sim/next.config.ts

@@ -417,6 +417,14 @@ const nextConfig: NextConfig = {
         source: '/r/:shortCode',
         destination: 'https://go.trybeluga.ai/:shortCode',
       },
+      {
+        source: '/ingest/static/:path*',
+        destination: 'https://us-assets.i.posthog.com/static/:path*',
+      },
+      {
+        source: '/ingest/:path*',
+        destination: 'https://us.i.posthog.com/:path*',
+      },
     ]
   },
 }