Add mock timeline-block checkbox

assets/checked.svg

@@ -0,0 +1,44 @@
+<?xml version="1.0" encoding="UTF-8" standalone="no"?>
+<svg
+   width="24"
+   height="24"
+   viewBox="0 0 24 24"
+   class="text-primary svelte-ztbs85"
+   stroke="transparent"
+   stroke-width="2"
+   role="img"
+   version="1.1"
+   id="svg1"
+   sodipodi:docname="checked.svg"
+   inkscape:version="1.4.4 (dcaf3e7d9e, 2026-05-05)"
+   xmlns:inkscape="http://www.inkscape.org/namespaces/inkscape"
+   xmlns:sodipodi="http://sodipodi.sourceforge.net/DTD/sodipodi-0.dtd"
+   xmlns="http://www.w3.org/2000/svg"
+   xmlns:svg="http://www.w3.org/2000/svg">
+  <defs
+     id="defs1" />
+  <sodipodi:namedview
+     id="namedview1"
+     pagecolor="#505050"
+     bordercolor="#eeeeee"
+     borderopacity="1"
+     inkscape:showpageshadow="0"
+     inkscape:pageopacity="0"
+     inkscape:pagecheckerboard="0"
+     inkscape:deskcolor="#505050"
+     inkscape:zoom="13.470055"
+     inkscape:cx="12.583468"
+     inkscape:cy="5.8277418"
+     inkscape:window-width="1555"
+     inkscape:window-height="1000"
+     inkscape:window-x="0"
+     inkscape:window-y="0"
+     inkscape:window-maximized="1"
+     inkscape:current-layer="svg1" />
+  <!---->
+  <!---->
+  <path
+     d="M12 2C6.5 2 2 6.5 2 12S6.5 22 12 22 22 17.5 22 12 17.5 2 12 2M10 17L5 12L6.41 10.59L10 14.17L17.59 6.58L19 8L10 17Z"
+     fill="currentColor"
+     id="path1" />
+</svg>