feat: portfolio redesign with i18n, RBC project showcase, CI/CD

- Add i18n support (EN/ZH) with language toggle
- Redesign header with education dropdown, contact copy buttons
- Add RBC project showcase with bullet points, skills highlighting
- Create terraform-drift placeholder page
- Add ProjectShowcase component with media toggle (image/video)
- Update experience timeline with action-driven descriptions
- Add Docker + Forgejo CI workflow for image builds
- Update K8s manifests for riotpiao.com ingress
- Add DESIGN.md documenting design system patterns

Dockerfile

@@ -0,0 +1,45 @@
+# Build stage
+FROM node:20-alpine AS builder
+
+WORKDIR /app
+
+# Copy package files
+COPY package.json pnpm-lock.yaml ./
+
+# Install pnpm
+RUN npm install -g pnpm
+
+# Install dependencies
+RUN pnpm install --frozen-lockfile
+
+# Copy source
+COPY . .
+
+# Build Next.js app
+RUN pnpm run build
+
+# Production stage
+FROM node:20-alpine
+
+WORKDIR /app
+
+# Install dumb-init for proper signal handling
+RUN apk add --no-cache dumb-init
+
+# Create non-root user
+RUN addgroup -g 1001 -S nodejs && \
+    adduser -S nextjs -u 1001
+
+# Copy built app from builder
+COPY --from=builder --chown=nextjs:nodejs /app/.next/standalone ./
+COPY --from=builder --chown=nextjs:nodejs /app/.next/static ./.next/static
+COPY --from=builder --chown=nextjs:nodejs /app/public ./public
+
+USER nextjs
+
+EXPOSE 3000
+
+ENV NODE_ENV=production
+
+ENTRYPOINT ["dumb-init", "--"]
+CMD ["node", "server.js"]