feat(smartrouter): Add destroy method to SmartRouter class.

ts/smartrouter.classes.smartrouter.ts

@@ -41,6 +41,11 @@ export class SmartRouter {
    */
   private basePath: string;
 
+  /**
+   * Reference to the event listener function for cleanup
+   */
+  private popstateListener: (event: PopStateEvent) => void;
+
   /**
    * Creates an instance of Router.
    */
@@ -53,10 +58,11 @@ export class SmartRouter {
     this.basePath = basePath;
 
     // lets subscribe to route changes
-    window.addEventListener('popstate', (popStateEventArg) => {
+    this.popstateListener = (popStateEventArg) => {
       popStateEventArg.preventDefault();
       this._handleRouteState();
-    });
+    };
+    window.addEventListener('popstate', this.popstateListener);
   }
 
   /**
@@ -119,4 +125,14 @@ export class SmartRouter {
       } as IRouteInfo); // not waiting here
     }
   }
+
+  /**
+   * Destroy the router instance, removing all external references
+   */
+  public destroy() {
+    // Remove the event listener for popstate
+    window.removeEventListener('popstate', this.popstateListener);
+    // Clear all routes
+    this.routes = [];
+  }
 }