Add appfooter

src/layout/appfooter.ts

@@ -2,6 +2,7 @@ import { Component } from '@angular/core';
 
 @Component({
     standalone:true,
+    selector: 'app-footer',
     template: `<div class="layout-footer">
         SAKAI by
         <a href="https://primeng.org" target="_blank" rel="noopener noreferrer" class="text-primary font-bold hover:underline">PrimeNG</a>