refactor: flatten monorepo to single web package (#12)

Flatten the pnpm monorepo (apps/web + packages/*) into a single web package at the repo root.

- Move app/lib/components/scripts/public to root; drop apps/web and packages/* wrappers
- Rewrite tsconfig paths (@infiplot/*) to ./lib/*; turbopack.root = __dirname
- Update Vercel (no root-directory) and Cloudflare (pnpm build:cf at root) deploy paths
- Regenerate pnpm-lock.yaml to drop stale workspace importers
- Bump engines.node to >=22 to match wrangler

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

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 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
+  }
+}