feat: use NEXT_PUBLIC_SITE_URL and remove redundant preconnect

Dockerfile

@@ -3,13 +3,15 @@ FROM node:20-alpine AS builder
 
 WORKDIR /app
 
-# Add build arguments for Umami
+# Add build arguments for Umami and Site URL
 ARG UMAMI_SCRIPT
 ARG UMAMI_ID
+ARG NEXT_PUBLIC_SITE_URL
 
 # Set environment variables for the build process
 ENV UMAMI_SCRIPT=$UMAMI_SCRIPT
 ENV UMAMI_ID=$UMAMI_ID
+ENV NEXT_PUBLIC_SITE_URL=$NEXT_PUBLIC_SITE_URL
 ENV NODE_ENV=production
 
 # Copy package files