Add R2 image storage, upload endpoint, and CDN support

- Backend: R2StorageService, upload controller (POST /api/upload)
- Frontend: CDN url helper, NEXT_PUBLIC_CDN_URL build arg
- Deploy: pass R2 secrets from Woodpecker CI to containers via .env
- Docs: update CLAUDE.md with CDN and upload conventions

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

frontend/.env.example

@@ -3,3 +3,6 @@ INTERNAL_API_URL=http://gb-prod-backend:5000
 
 # URL бэкенда для проксирования /api/* в локальной разработке (не задавать на сервере!)
 # LOCAL_API_URL=http://localhost:5000
+
+# CDN URL для изображений (Cloudflare R2)
+NEXT_PUBLIC_CDN_URL=https://cdn.goodbrick.com.ua

frontend/Dockerfile

@@ -7,6 +7,7 @@ FROM node:20-alpine AS builder
 WORKDIR /app
 ARG NEXT_PUBLIC_POSTHOG_KEY
 ARG NEXT_PUBLIC_POSTHOG_HOST
+ARG NEXT_PUBLIC_CDN_URL
 COPY --from=deps /app/node_modules ./node_modules
 COPY . .
 RUN npm run build

frontend/next.config.ts

@@ -2,6 +2,11 @@ import type { NextConfig } from "next";
 
 const nextConfig: NextConfig = {
   output: "standalone",
+  images: {
+    remotePatterns: [
+      { protocol: "https", hostname: "cdn.goodbrick.com.ua" },
+    ],
+  },
   async rewrites() {
     const apiUrl = process.env.LOCAL_API_URL;
     if (!apiUrl) return [];

frontend/public/robots.txt

@@ -0,0 +1,5 @@
+User-agent: *
+Allow: /
+Allow: /_next/image
+
+Sitemap: https://new.goodbrick.com.ua/sitemap.xml

frontend/src/lib/cdn.ts

@@ -0,0 +1,6 @@
+const CDN_BASE_URL =
+  process.env.NEXT_PUBLIC_CDN_URL || "https://cdn.goodbrick.com.ua";
+
+export function cdnUrl(path: string): string {
+  return `${CDN_BASE_URL.replace(/\/+$/, "")}/${path.replace(/^\/+/, "")}`;
+}