feat: add Cloudflare Workers deployment alongside Vercel

InfiPlot now deploys to either Vercel or Cloudflare Workers — both
targets are first-class. The project is fully stateless (sessions live
on the client), so the Cloudflare side needs only Workers + Workers
Assets and zero D1/KV/R2.

- apps/web/wrangler.jsonc — nodejs_compat, Assets binding, 60s CPU
  limit (Workers Paid required; matches vercel.json maxDuration). I/O
  wait does not count against this budget — fits the LLM-bound
  workload that's most of the runtime.
- apps/web/open-next.config.ts — minimal defineCloudflareConfig (no
  cache needed since the engine is stateless).
- apps/web/package.json — added build:cf / preview:cf / deploy:cf via
  @opennextjs/cloudflare + wrangler (both devDeps); sharp moved from
  dependencies to devDependencies (only used by the manual
  optimize-home-images.mjs / localize-firstact-images.mjs scripts now).
- .gitignore — .open-next, .wrangler, .dev.vars.
- READMEs (3 langs) — Deploy to Cloudflare button next to Vercel,
  plus a Cloudflare section in the env-var setup (wrangler secret put
  + Cloudflare Access for staging access control).

Verified: pnpm typecheck + pnpm build (Vercel path) + pnpm build:cf
(OpenNext bundle: worker 4 KB, server 24 MB, assets 32 MB / 186
files — all within Workers limits) + pnpm preview:cf with the full
play loop (start → scene → background click → CORS-clean Canvas
annotation via Runware CDN → vision LLM → insert-beat) all green.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

apps/web/open-next.config.ts

@@ -0,0 +1,5 @@
+import { defineCloudflareConfig } from "@opennextjs/cloudflare";
+
+// Minimal config — the project is fully stateless (sessions live on the
+// client), so no R2/KV/D1 incremental cache is needed.
+export default defineCloudflareConfig();

apps/web/package.json

@@ -8,7 +8,10 @@
     "build": "next build",
     "start": "next start",
     "lint": "next lint",
-    "typecheck": "tsc --noEmit"
+    "typecheck": "tsc --noEmit",
+    "build:cf": "opennextjs-cloudflare build",
+    "preview:cf": "opennextjs-cloudflare preview",
+    "deploy:cf": "opennextjs-cloudflare deploy"
   },
   "dependencies": {
     "@infiplot/ai-client": "workspace:*",
@@ -16,16 +19,18 @@
     "@infiplot/types": "workspace:*",
     "next": "^16.0.0",
     "react": "^19.0.0",
-    "react-dom": "^19.0.0",
-    "sharp": "^0.33.5"
+    "react-dom": "^19.0.0"
   },
   "devDependencies": {
+    "@opennextjs/cloudflare": "^1.19.11",
+    "sharp": "^0.33.5",
     "@types/node": "^22.9.0",
     "@types/react": "^19.0.0",
     "@types/react-dom": "^19.0.0",
     "autoprefixer": "^10.4.20",
     "postcss": "^8.4.49",
     "tailwindcss": "^3.4.15",
-    "typescript": "^5.6.3"
+    "typescript": "^5.6.3",
+    "wrangler": "^4.96.0"
   }
 }

apps/web/wrangler.jsonc

@@ -0,0 +1,20 @@
+{
+  "$schema": "node_modules/wrangler/config-schema.json",
+  "name": "infiplot",
+  "main": ".open-next/worker.js",
+  "compatibility_date": "2025-03-25",
+  "compatibility_flags": ["nodejs_compat"],
+  "assets": {
+    "binding": "ASSETS",
+    "directory": ".open-next/assets"
+  },
+  "observability": {
+    "enabled": true
+  },
+  // 60s mirrors apps/web/vercel.json maxDuration for the scene pipeline tail
+  // (multi-agent LLM, ~30-45s p95). Requires Workers Paid — Free is capped
+  // at 10ms CPU. I/O wait does not count against this budget.
+  "limits": {
+    "cpu_ms": 60000
+  }
+}