feat: we have a functional prototype

client/src/app/error/error.component.ts

@@ -0,0 +1,14 @@
+import { Component, input } from "@angular/core";
+
+/**
+ *
+ */
+@Component({
+  imports:     [],
+  selector:    'app-error',
+  styleUrl:    './error.component.css',
+  templateUrl: "./error.component.html",
+})
+export class ErrorComponent {
+  public error = input.required<string>();
+}