Modify tile delete button for touch

Prototype of larger delete button for sprites, costumes and sounds to better support touch devices.

I split it out from `CloseButton` as it made the changes simpler, and we may end up going in a different direction (open context menu).

src/components/delete-button/delete-button.css

@@ -0,0 +1,48 @@
+@import "../../css/colors.css";
+@import "../../css/units.css";
+
+/* the delete button has .25rem invisible 'slop' around the visible button
+   to make it easier to tap on a touch device */
+.delete-button {
+    display: flex;
+    align-items: center;
+    justify-content: center;
+
+    overflow: hidden;  /* Mask the icon animation */
+    width: 2rem;
+    height: 2rem;
+    user-select: none;
+    cursor: pointer;
+    transition: all 0.15s ease-out;
+
+}
+
+/* .delete-button.large:hover {
+    transform: scale(1.1, 1.1);
+    box-shadow: 0 0 0 4px $ui-black-transparent;
+} */
+
+.delete-button-visible {
+  display: flex;
+  align-items: center;
+  justify-content: center;
+
+  overflow: hidden;  /* Mask the icon animation */
+  width: 1.75rem;
+  height: 1.75rem;
+  box-shadow: 0px 0px 0px 2px $motion-transparent;
+  background-color: $motion-primary;
+  color: $ui-white;
+  border-radius: 50%;
+  font-family: "Helvetica Neue", Helvetica, Arial, sans-serif;
+  user-select: none;
+  cursor: pointer;
+  transition: all 0.15s ease-out;
+}
+
+.delete-icon {
+    position: relative;
+    margin: 0.25rem;
+    user-select: none;
+    transform-origin: 50%;
+}