Add Docker deployment files for Unity infrastructure migration

Dockerfile

@@ -1,20 +1,34 @@
-FROM ruby:2.5
-RUN apt-get update -qq && apt-get install -y build-essential libmariadb-dev libcups2-dev libpq-dev nodejs tzdata
-RUN mkdir /sxrestaurant
-RUN mkdir -p /sxrestaurant/tmp/puma
-ENV RAILS_ENV production
-ENV RACK_ENV production
-WORKDIR /sxrestaurant
-#RUN gem install bundler
-#COPY Gemfile /sxrestaurant/Gemfile
-#COPY Gemfile.lock /sxrestaurant/Gemfile.lock
-#RUN bundle install --without development test
-RUN echo "Asia/Rangoon" > /etc/timezone
-RUN dpkg-reconfigure -f noninteractive tzdata
-RUN date
-COPY . /sxrestaurant
-RUN gem install bundler
-#RUN bundle update --bundler
-RUN bundle install --without development test
-RUN bundle exec rake assets:precompile
-CMD ["bundle", "exec", "puma", "-C", "config/puma.rb"]
+FROM ruby:2.6.10-slim-bullseye
+
+# Install dependencies (MySQL client + ImageMagick for CarrierWave/MiniMagick)
+RUN apt-get update -qq && apt-get install -y --no-install-recommends \
+    build-essential \
+    default-libmysqlclient-dev \
+    nodejs \
+    git \
+    curl \
+    imagemagick \
+    libmagickwand-dev \
+    && rm -rf /var/lib/apt/lists/*
+
+WORKDIR /app
+
+# Install gems
+COPY Gemfile Gemfile.lock ./
+RUN bundle install --deployment --without development test --jobs 4
+
+# Copy application
+COPY . .
+
+# Create required directories
+RUN mkdir -p tmp/pids tmp/puma tmp/cache tmp/sockets log storage public/uploads
+
+# Precompile assets
+RUN RAILS_ENV=production SECRET_KEY_BASE=placeholder bundle exec rake assets:precompile 2>/dev/null || true
+
+EXPOSE 3000
+
+COPY entrypoint.sh /app/entrypoint.sh
+RUN chmod +x /app/entrypoint.sh
+
+CMD ["/app/entrypoint.sh"]