build: add Docker and nginx configuration for deployment

Added Dockerfile.web for containerizing the web application and nginx.conf
for serving the application in production. Also included .gitea/ directory
for CI/CD configuration.

Dockerfile.web

@@ -0,0 +1,16 @@
+FROM node:20-alpine AS builder
+
+WORKDIR /app
+
+COPY package.json package-lock.json ./
+RUN npm ci
+
+COPY . .
+RUN npm run build
+
+FROM nginx:1.27-alpine
+
+COPY nginx.conf /etc/nginx/conf.d/default.conf
+COPY --from=builder /app/dist /usr/share/nginx/html
+
+EXPOSE 80