fix: added _includes

_includes/embed/twitch.html

@@ -0,0 +1,4 @@
+<iframe class="embed-video twitch lazyload"
+  src="https://player.twitch.tv/?video={{ include.id }}&parent={{ site.url | split: '://' | last | remove: '/' }}"
+  frameborder="0" allowfullscreen="true"
+  scrolling="no"></iframe>

_includes/embed/youtube.html

@@ -0,0 +1,6 @@
+<iframe class="embed-video youtube lazyload"
+  src="https://www.youtube.com/embed/{{ include.id }}"
+  title="YouTube video player"
+  frameborder="0"
+  allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture"
+  allowfullscreen></iframe>