fix(vercel): rewrite /ingest/* with trailing slash to PostHog

PostHog's JS SDK POSTs to /ingest/s/, /ingest/e/, /ingest/i/v0/e/ with
trailing slashes. The existing /ingest/:path* rewrite matched only
no-trailing-slash paths, so Vercel served cached 404s for ~27/hr —
540 events in a 20h window, analytics data silently dropped.

Adds :path+/ variant before the :path* rule. Also drops the dead
/ingest/decide rule (already covered by the wildcard).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: Mlaz-code

vercel.json

@@ -34,7 +34,7 @@
   ],
   "rewrites": [
     { "source": "/ingest/static/:path*", "destination": "https://us-assets.i.posthog.com/static/:path*" },
-    { "source": "/ingest/:path*", "destination": "https://us.i.posthog.com/:path*" },
-    { "source": "/ingest/decide", "destination": "https://us.i.posthog.com/decide" }
+    { "source": "/ingest/:path+/", "destination": "https://us.i.posthog.com/:path+/" },
+    { "source": "/ingest/:path*", "destination": "https://us.i.posthog.com/:path*" }
   ]
 }