Add build script to slim down docker images

Reviewed-on: #2

Dockerfile

@@ -1,9 +1,11 @@
-FROM node:18 as build
+FROM node:22 as build
 WORKDIR /app
 COPY package.json package.json
+COPY .yarnrc.yml .yarnrc.yml
 COPY yarn.lock yarn.lock
 COPY tsconfig.json tsconfig.json
 
+RUN corepack enable
 RUN yarn install
 
 COPY src ./src

build.sh

@@ -0,0 +1,12 @@
+#!/usr/bin/env bash
+
+if command -v yarn >/dev/null 2>&1; then
+    echo "yarn is available"
+else
+    echo "yarn is not installed" >&2
+    exit 1
+fi
+
+yarn install
+
+yarn build