feat: Update Dockerfile for multi-platform support and add nginx configuration

Dockerfile

@@ -1,4 +1,4 @@
-FROM node:lts-alpine3.23 AS builder
+FROM --platform=$BUILDPLATFORM node:lts-alpine3.23 AS builder
 
 WORKDIR /app
 
@@ -9,13 +9,15 @@ RUN npm install
 COPY . .
 RUN npm run build
 
-FROM nginx:stable-alpine AS production
+FROM --platform=$TARGETPLATFORM nginx:stable-alpine AS production
 
 RUN apk add --no-cache gettext
 
 RUN rm -rf /usr/share/nginx/html/*
 COPY --from=builder /app/dist /usr/share/nginx/html
 
+COPY nginx.conf /etc/nginx/conf.d/default.conf
+
 COPY public/env.template.js /usr/share/nginx/html/env.template.js
 COPY docker-entrypoint.sh /docker-entrypoint.sh
 RUN chmod +x /docker-entrypoint.sh