Separate docs-nav into new component

Since same markup will be needed for desktop
and mobile menus.

frontend/src/app/components/docs/api-docs-nav.component.ts

@@ -0,0 +1,17 @@
+import { Component, OnInit, Input } from '@angular/core';
+
+@Component({
+  selector: 'app-api-docs-nav',
+  templateUrl: './api-docs-nav.component.html',
+  styleUrls: ['./api-docs-nav.component.scss']
+})
+export class ApiDocsNavComponent implements OnInit {
+
+  @Input() network: any;
+
+  constructor() { }
+
+  ngOnInit(): void {
+  }
+
+}