fix: add globalEnv to turbo.json to fix stale rewrite cache in Docker builds

Without explicit globalEnv, Turborepo could cache Next.js builds
with wrong INTERNAL_API_URL, causing web container to proxy to
127.0.0.1 instead of the Docker service name.

Co-authored-by: Cursor <cursoragent@cursor.com>

turbo.json

@@ -1,6 +1,7 @@
 {
   "$schema": "https://turbo.build/schema.json",
   "globalDependencies": [".env"],
+  "globalEnv": ["INTERNAL_API_URL", "API_URL", "NEXT_PUBLIC_SUPABASE_URL", "NEXT_PUBLIC_SUPABASE_ANON_KEY", "NEXT_PUBLIC_APP_URL"],
   "tasks": {
     "build": {
       "dependsOn": ["^build"],