fix: Update nginx config to use dynamic DNS resolution

- Replace upstream blocks with resolver directive
- Use variables for backend addresses to avoid startup errors
- Simplify configuration with single server block
- Add health check endpoint

server/api/node_modules/@sinonjs/commons/lib/class-name.js

@@ -0,0 +1,13 @@
+"use strict";
+
+/**
+ * Returns a display name for a value from a constructor
+ * @param  {object} value A value to examine
+ * @returns {(string|null)} A string or null
+ */
+function className(value) {
+    const name = value.constructor && value.constructor.name;
+    return name || null;
+}
+
+module.exports = className;