fix: install all deps for webui build including devDependencies

The Next.js build requires TypeScript, @types/*, tailwindcss and other
devDependencies. Changed npm ci --only=production to npm ci.

Made-with: Cursor

backend/webui/Dockerfile

@@ -5,7 +5,7 @@ RUN apk add --no-cache libc6-compat
 WORKDIR /app
 
 COPY package.json package-lock.json* ./
-RUN npm ci --only=production
+RUN npm ci
 
 FROM base AS builder
 WORKDIR /app