Add sb server host as response header

src/middleware/hostHeader.ts

@@ -0,0 +1,7 @@
+import { NextFunction, Request, Response } from "express";
+import os from "os";
+
+export function hostHeader(req: Request, res: Response, next: NextFunction): void {
+    res.header("SBSERVER-HOST", os.hostname());
+    next();
+}