Allow Node.js APIs required by various build-time integrations.

I *think* the run time ones are all Node-free, but Cloudflare’s Node.js compatibility layer should catch them.

astro.config.ts

@@ -36,6 +36,10 @@ export default defineConfig({
   vite: {
 	build: {
       assetsInlineLimit: 0
+	},
+	ssr: {
+		// These are all Node.js APIs that don't work on Cloudflare. They are only used at build-time, but Astro doesn't understand that they won't be needed in the Cloudflare environment, so they have to be explicitly allowed.
+		external: ["child_process", "crypto", "fs", "module", "node:buffer", "node:child_process", "node:events", "node:fs", "node:os", "node:process", "node:path", "node:stream", "node:stream/promises", "node:string_decoder", "node:timers/promises", "node:url", "node:util", "node:tty", "node:v8", "os", "path", "stream", "string_decoder", "tty", "url", "util", "worker_threads","process"]
 	}
 	},