add initial project for frontend

Signed-off-by: Tobias Erbshäußer <tobias@tesoft.dev>

frontend/src/components/button.njk

@@ -0,0 +1,11 @@
+<template id="tesoft-button-template">
+    <style>
+        @import "src/styles/default.css";
+    </style>
+
+    <button>
+        <slot></slot>
+    </button>
+</template>
+
+<script src="/src/components/button.ts" type="module"></script>

frontend/src/components/button.ts

@@ -0,0 +1,15 @@
+import {TesoftComponent} from "../scripts/main.ts";
+
+export class TesoftButton extends TesoftComponent {
+    constructor() {
+        super();
+
+        const template = document.getElementById("tesoft-button-template") as HTMLTemplateElement;
+        const templateContent = template.content;
+
+        const shadowRoot = this.attachShadow({mode: "open"});
+        shadowRoot.appendChild(templateContent.cloneNode(true));
+    }
+}
+
+customElements.define("tesoft-button", TesoftButton);