chore: clean up environment variable usage and formatting in configuration files

- Updated docker-compose.yaml to use double quotes for version and port mappings.
- Removed DEPLOYMENT_PROVIDER from global environment variables in turbo.json and Dockerfile.
- Adjusted dashboard build command in package.json to remove DEPLOYMENT_PROVIDER.
- Cleaned up .env.example by removing the DEPLOYMENT_PROVIDER comment.
- Simplified SvelteKit adapter condition in svelte.config.js.

apps/dashboard/Dockerfile

@@ -31,7 +31,6 @@ COPY apps/dashboard ./apps/dashboard
 
 # Set env vars for SvelteKit to use Node adapter
 ENV PUBLIC_IS_SELFHOSTED=true \
-    DEPLOYMENT_PROVIDER=docker \
     PUBLIC_SUPABASE_URL=$PUBLIC_SUPABASE_URL \
     PUBLIC_SUPABASE_ANON_KEY=$PUBLIC_SUPABASE_ANON_KEY \
     PRIVATE_SUPABASE_SERVICE_ROLE=$PRIVATE_SUPABASE_SERVICE_ROLE \
@@ -68,7 +67,6 @@ EXPOSE 3000
 # Set environment variables for production
 ENV NODE_ENV=production \
     PUBLIC_IS_SELFHOSTED=true \
-    DEPLOYMENT_PROVIDER=docker \
     PUBLIC_SUPABASE_URL=$PUBLIC_SUPABASE_URL \
     PUBLIC_SUPABASE_ANON_KEY=$PUBLIC_SUPABASE_ANON_KEY \
     PRIVATE_SUPABASE_SERVICE_ROLE=$PRIVATE_SUPABASE_SERVICE_ROLE \