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/asynckit/lib/abort.js

@@ -0,0 +1,29 @@
+// API
+module.exports = abort;
+
+/**
+ * Aborts leftover active jobs
+ *
+ * @param {object} state - current state object
+ */
+function abort(state)
+{
+  Object.keys(state.jobs).forEach(clean.bind(state));
+
+  // reset leftover jobs
+  state.jobs = {};
+}
+
+/**
+ * Cleans up leftover job by invoking abort function for the provided job id
+ *
+ * @this  state
+ * @param {string|number} key - job id to abort
+ */
+function clean(key)
+{
+  if (typeof this.jobs[key] == 'function')
+  {
+    this.jobs[key]();
+  }
+}