feat: adds docker-based dev environment (#18)

* feat: adds docker-based dev environment

* docs: updates Docker command help

* fix local dev

frontend/Dockerfile

@@ -0,0 +1,16 @@
+# Frontend Development Dockerfile
+FROM node:22-alpine
+
+# Accept build argument for pnpm store path
+ARG PNPM_STORE_PATH=/root/.local/share/pnpm/store
+
+# Install pnpm at specific version (matching package.json)
+RUN corepack enable && corepack install -g pnpm@10.26.2
+
+RUN pnpm config set store-dir ${PNPM_STORE_PATH}
+
+# Set working directory
+WORKDIR /app
+
+# Expose Next.js dev server port
+EXPOSE 3000