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/speedometer.js

@@ -0,0 +1,55 @@
+'use strict';
+
+/**
+ * Calculate data maxRate
+ * @param {Number} [samplesCount= 10]
+ * @param {Number} [min= 1000]
+ * @returns {Function}
+ */
+function speedometer(samplesCount, min) {
+  samplesCount = samplesCount || 10;
+  const bytes = new Array(samplesCount);
+  const timestamps = new Array(samplesCount);
+  let head = 0;
+  let tail = 0;
+  let firstSampleTS;
+
+  min = min !== undefined ? min : 1000;
+
+  return function push(chunkLength) {
+    const now = Date.now();
+
+    const startedAt = timestamps[tail];
+
+    if (!firstSampleTS) {
+      firstSampleTS = now;
+    }
+
+    bytes[head] = chunkLength;
+    timestamps[head] = now;
+
+    let i = tail;
+    let bytesCount = 0;
+
+    while (i !== head) {
+      bytesCount += bytes[i++];
+      i = i % samplesCount;
+    }
+
+    head = (head + 1) % samplesCount;
+
+    if (head === tail) {
+      tail = (tail + 1) % samplesCount;
+    }
+
+    if (now - firstSampleTS < min) {
+      return;
+    }
+
+    const passed = startedAt && now - startedAt;
+
+    return passed ? Math.round(bytesCount * 1000 / passed) : undefined;
+  };
+}
+
+export default speedometer;