chore: add project dependencies and configuration files

Initial setup of project dependencies including axios, express, dotenv, and other supporting packages. Added configuration files and documentation for project setup and usage.

node_modules/axios/lib/helpers/throttle.js

@@ -0,0 +1,44 @@
+/**
+ * Throttle decorator
+ * @param {Function} fn
+ * @param {Number} freq
+ * @return {Function}
+ */
+function throttle(fn, freq) {
+  let timestamp = 0;
+  let threshold = 1000 / freq;
+  let lastArgs;
+  let timer;
+
+  const invoke = (args, now = Date.now()) => {
+    timestamp = now;
+    lastArgs = null;
+    if (timer) {
+      clearTimeout(timer);
+      timer = null;
+    }
+    fn.apply(null, args);
+  }
+
+  const throttled = (...args) => {
+    const now = Date.now();
+    const passed = now - timestamp;
+    if ( passed >= threshold) {
+      invoke(args, now);
+    } else {
+      lastArgs = args;
+      if (!timer) {
+        timer = setTimeout(() => {
+          timer = null;
+          invoke(lastArgs)
+        }, threshold - passed);
+      }
+    }
+  }
+
+  const flush = () => lastArgs && invoke(lastArgs);
+
+  return [throttled, flush];
+}
+
+export default throttle;