added initial istio BLAHAJ code

apps/blahaj-common/app.mjs

@@ -0,0 +1,31 @@
+// bun, es modules, minimal deps; one file serves all three services
+import http from 'http';
+
+const serviceName = process.env.SERVICE_NAME || 'blahaj';
+const emoji = process.env.SERVICE_EMOJI || '🦈';
+const friend = process.env.FRIEND_NAME || 'sea-friend';
+const port = Number(process.env.PORT || 8080);
+
+const ascii = `
+          __
+      _.-'  \\
+  _.-'  _.-'\\)   ${emoji}  // ascii blahaj says hi!
+ (____.-'             ~ waves ~
+`;
+
+const server = http.createServer((req, res) => {
+	const path = req.url || '/';
+	const message = {
+		service: serviceName,
+		says: `hello, ${friend}! i am ${serviceName} ✨`,
+		path,
+		mascot: 'BLÅHAJ',
+		fun: 'soft, cuddly shark energy',
+	};
+	res.setHeader('content-type', 'application/json; charset=utf-8');
+	res.end(JSON.stringify({ message, ascii }));
+});
+
+server.listen(port, () => {
+	console.log(`${serviceName} listening on ${port};`);
+});