Adds native share button

Replaces the existing share buttons with a native share button implemented using the Web Share API.

This simplifies the code, removes dependency on external libraries, and provides a more consistent user experience across different platforms.
The old share buttons are removed from the config file.

static/js/share-button.js

@@ -0,0 +1,29 @@
+class ShareButton extends HTMLElement {
+  static register(tagName) {
+    if ("customElements" in window && window.navigator.share) {
+      customElements.define(tagName || "share-button", ShareButton);
+    }
+  }
+
+  connectedCallback() {
+    this.button.addEventListener("click", this.share);
+  }
+
+  get button() {
+    return this.querySelector("button");
+  }
+
+  share = () => {
+    const root = this.getRootNode();
+    window.navigator
+      .share({
+        title: root.title,
+        text: root.title,
+        url: window.location.href,
+      })
+      .then(() => console.log("Page was succesffuly shared"))
+      .catch((error) => console.log(error));
+  };
+}
+
+ShareButton.register();