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>

scripts/optimize-home-images.mjs

@@ -0,0 +1,42 @@
+#!/usr/bin/env node
+/**
+ * Compresses the freshly generated public/home/*.png into much
+ * smaller .webp files alongside them, then deletes the originals.
+ * Output webps target ~1200px on the long edge and quality 78.
+ */
+
+import { readdirSync, statSync, unlinkSync } from "node:fs";
+import { resolve, dirname, extname, basename } from "node:path";
+import { fileURLToPath } from "node:url";
+import sharp from "sharp";
+
+const __dirname = dirname(fileURLToPath(import.meta.url));
+const DIR = resolve(__dirname, "..", "public", "home");
+
+const MAX_EDGE = 1200;
+const QUALITY = 78;
+
+const files = readdirSync(DIR).filter((f) => f.toLowerCase().endsWith(".png"));
+let totalIn = 0;
+let totalOut = 0;
+
+for (const f of files) {
+  const inPath = resolve(DIR, f);
+  const outPath = resolve(DIR, basename(f, extname(f)) + ".webp");
+  const inSize = statSync(inPath).size;
+  totalIn += inSize;
+
+  const img = sharp(inPath);
+  const meta = await img.metadata();
+  const longEdge = Math.max(meta.width ?? 0, meta.height ?? 0);
+  const resized = longEdge > MAX_EDGE ? img.resize({ width: meta.width >= meta.height ? MAX_EDGE : undefined, height: meta.height > meta.width ? MAX_EDGE : undefined }) : img;
+  await resized.webp({ quality: QUALITY, effort: 5 }).toFile(outPath);
+  const outSize = statSync(outPath).size;
+  totalOut += outSize;
+  console.log(`${f.padEnd(16)} ${(inSize / 1024).toFixed(0).padStart(5)} KB → ${(outSize / 1024).toFixed(0).padStart(4)} KB`);
+  unlinkSync(inPath);
+}
+
+console.log(
+  `\nTotal: ${(totalIn / 1024 / 1024).toFixed(1)} MB → ${(totalOut / 1024 / 1024).toFixed(2)} MB`,
+);