fix(x402): add tsdown config to build middleware entry point (#48)

* fix(x402): add tsdown config to build middleware entry point

* adds optimizeDeps.exclude and ssr.optimizeDeps.exclude for @emdash-cms/x402 in the integration's Vite config

* fix CI typecheck

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Co-authored-by: Matt Kane <mkane@cloudflare.com>

packages/x402/tsdown.config.ts

@@ -0,0 +1,10 @@
+import { defineConfig } from "tsdown";
+
+export default defineConfig({
+	entry: ["src/index.ts", "src/middleware.ts"],
+	format: ["esm"],
+	dts: true,
+	clean: true,
+	inlineOnly: false,
+	external: ["astro:middleware", "virtual:x402/config"],
+});