test: adapt caddy testing environment into a smoke test

Signed-off-by: Xe Iaso <me@xeiaso.net>

test/caddy/test.mjs

@@ -0,0 +1,27 @@
+async function testWithUserAgent(userAgent) {
+  const statusCode =
+    await fetch("https://relayd.local.cetacean.club:8443/reqmeta", {
+      headers: {
+        "User-Agent": userAgent,
+      }
+    })
+      .then(resp => resp.status);
+  return statusCode;
+}
+
+const codes = {
+  Mozilla: await testWithUserAgent("Mozilla"),
+  curl: await testWithUserAgent("curl"),
+}
+
+const expected = {
+  Mozilla: 401,
+  curl: 200,
+};
+
+console.log("Mozilla:", codes.Mozilla);
+console.log("curl:   ", codes.curl);
+
+if (JSON.stringify(codes) !== JSON.stringify(expected)) {
+  throw new Error(`wanted ${JSON.stringify(expected)}, got: ${JSON.stringify(codes)}`);
+}