Fix Cloudflare OG: ship .wasm as module imports, not inlined bytes

[scottmessinger]

Problem

OG image generation fails on Cloudflare Workers with:

CompileError: WebAssembly.instantiate(): Wasm code generation disallowed by embedder

src/og.ts already does the right thing — it imports the resvg/yoga wasm as modules and calls initWasm(resvgWasm as WebAssembly.Module) / initYoga(yogaWasm). But bin/esbuild.js used loader: { ".wasm": "binary" }, which embeds each .wasm as a Uint8Array in the published dist. At runtime resvg/yoga therefore receive raw bytes and call WebAssembly.instantiate(bytes), which Cloudflare's workerd forbids (it disallows compiling wasm at runtime — only precompiled WebAssembly.Modules may be instantiated).

Fix

• bin/esbuild.js: mark .wasm as external instead of inlining it as binary. The imports now survive into dist/index.js as real ES module imports (import … from "../vendors/*.wasm").
• package.json: ship vendors/ alongside dist/ so those import paths resolve from the installed package.

The downstream bundler (Vite + @astrojs/cloudflare) then compiles these .wasm imports into precompiled WebAssembly.Module instances at deploy time, which workerd accepts. dist/index.js drops from ~2.2 MB to ~393 KB now that the wasm is no longer base64-inlined.

Verification

Consumed from the marketing site (Astro + @astrojs/cloudflare):

• Prod build emits resvg.*.wasm / yoga.*.wasm as separate module files and the server chunk imports them — no inlined bytes.
• OG route renders a valid PNG locally.

🤖 Generated with Claude Code

[Copilot]

Pull request overview

Fixes Cloudflare Workers OG image generation by switching the build from inlining .wasm files to leaving them as ES module imports that the downstream bundler can compile into precompiled WebAssembly.Module instances (required by workerd, which disallows runtime wasm compilation).

Changes:

• bin/esbuild.js: mark .wasm as external so imports remain real ES module imports in dist/index.js instead of being copied/inlined.
• package.json: ship vendors/ so the emitted ../vendors/*.wasm import paths resolve from the installed package, and add a prepare script so the build runs after install.

Reviewed changes

Copilot reviewed 1 out of 2 changed files in this pull request and generated no comments.

File	Description
packages/workers-og/bin/esbuild.js	Replaces the .wasm loader config with external: ["*.wasm"] plus an explanatory comment.
packages/workers-og/package.json	Includes vendors in published files and adds a prepare script invoking pnpm build.

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