perf(backoff): optimize linear backoff using closure (#243)

- Remove lodash dependency for faster property access
- Pre-calculate range in closure to avoid repeated subtraction on each call
- Add early return optimization for constant values (min === max)
- Use modern JS features (default parameters, arrow functions)

The range calculation is moved from the hot path (next() function) to
the closure scope, ensuring it's computed only once when the backoff
function is created rather than on every invocation.

Author: Ayoub-Mabrouk

lib/backoff/linear.js

@@ -1,18 +1,11 @@
-const get = require('lodash').get;
-
-module.exports = function (options) {
-  const min = get(options, 'min', 1000);
-  const max = get(options, 'max', min);
+module.exports = function (options = {}) {
+  const min = options.min || 1000;
+  const max = options.max || min;
+  const range = max - min;
 
   function next() {
-    return Math.floor(Math.random() * (max - min + 1) + min);
+    return range === 0 ? min : Math.floor(Math.random() * (range + 1) + min);
   }
 
-  // eslint-disable-next-line no-empty-function
-  function reset() {}
-
-  return {
-    next,
-    reset,
-  };
+  return { next, reset: () => {} };
 };