Refactor code structure for improved readability and maintainability

Dockerfile

@@ -0,0 +1,64 @@
+# Multi-stage build for production optimization
+FROM node:18-alpine AS development
+
+# Set working directory
+WORKDIR /usr/src/app
+
+# Copy package files
+COPY package*.json yarn.lock ./
+
+# Install dependencies
+RUN yarn install --frozen-lockfile
+
+# Copy source code
+COPY . .
+
+# Expose port
+EXPOSE 3000
+
+# Development command
+CMD ["yarn", "start:dev"]
+
+# Production build stage
+FROM node:18-alpine AS build
+
+WORKDIR /usr/src/app
+
+# Copy package files
+COPY package*.json yarn.lock ./
+
+# Install dependencies
+RUN yarn install --frozen-lockfile
+
+# Copy source code
+COPY . .
+
+# Build the application
+RUN yarn build
+
+# Production stage
+FROM node:18-alpine AS production
+
+WORKDIR /usr/src/app
+
+# Copy package files
+COPY package*.json yarn.lock ./
+
+# Install only production dependencies
+RUN yarn install --frozen-lockfile --production && yarn cache clean
+
+# Copy built application
+COPY --from=build /usr/src/app/dist ./dist
+
+# Create non-root user
+RUN addgroup -g 1001 -S nodejs
+RUN adduser -S nestjs -u 1001
+
+# Change ownership of the app directory
+USER nestjs
+
+# Expose port
+EXPOSE 3000
+
+# Production command
+CMD ["node", "dist/main"]