feat: Add initial frontend dependencies, base CSS, and Gitea Docker build workflow.

frontend/Dockerfile

@@ -0,0 +1,13 @@
+# Build stage
+FROM node:18-alpine AS build
+WORKDIR /app
+COPY package*.json ./
+RUN npm install
+COPY . .
+RUN npm run build
+
+# Run stage
+FROM nginx:alpine
+COPY --from=build /app/dist /usr/share/nginx/html
+EXPOSE 80
+CMD ["nginx", "-g", "daemon off;"]