feat: монорепо миграция, Discover/SearxNG улучшения

- Миграция на монорепозиторий (apps/frontend, apps/chat-service, etc.)
- Discover: проверка SearxNG, понятное empty state при ненастроенном поиске
- searxng.ts: валидация URL, проверка JSON-ответа, авто-добавление http://
- docker/searxng-config: настройки для JSON API SearxNG

Co-authored-by: Cursor <cursoragent@cursor.com>

apps/auth-mcs/Dockerfile

@@ -0,0 +1,34 @@
+FROM node:20-alpine AS base
+
+FROM base AS deps
+WORKDIR /app
+COPY package.json package-lock.json* ./
+RUN npm ci
+
+FROM base AS builder
+WORKDIR /app
+COPY --from=deps /app/node_modules ./node_modules
+COPY . .
+
+# Сборка без env check для статики
+ENV NEXT_TELEMETRY_DISABLED=1
+RUN npm run build
+
+FROM base AS runner
+WORKDIR /app
+ENV NODE_ENV=production
+ENV NEXT_TELEMETRY_DISABLED=1
+
+RUN addgroup --system --gid 1001 nodejs
+RUN adduser --system --uid 1001 nextjs
+
+COPY --from=builder /app/public ./public
+COPY --from=builder --chown=nextjs:nodejs /app/.next/standalone ./
+COPY --from=builder --chown=nextjs:nodejs /app/.next/static ./.next/static
+
+USER nextjs
+EXPOSE 3001
+ENV PORT=3001
+ENV HOSTNAME="0.0.0.0"
+
+CMD ["node", "server.js"]