Add UI enhancements (#185)

This PR:
* Adds color coded markers on the confidence slider
* Changes the confidence slider visual to be more intuitive (the highlight region covers the visible structures)
* Gives the tag container a max height so that too many tags doesn't reduce the image to 0 size

Signed-off-by: Justin Georgi <justin.georgi@gmail.com>

Reviewed-on: #185

src/css/detect.css

@@ -89,6 +89,26 @@
   display: none;
 }
 
+.level-slide-marker {
+  border: var(--avn-slide-marker-border);
+  position: absolute;
+  top: 0%;
+  height: 100%;
+  left: var(--avn-slide-marker-position);
+}
+
+.range-bar {
+  background: var(--avn-theme-color);
+}
+
+.range-bar-active {
+  background: rgba(255,255,255,.8);
+}
+
+.dark .range-bar-active {
+  background: rgba(0,0,0,.8);
+}
+
 .image-menu {
   grid-area: menu-view;
   margin: 5px;
@@ -170,6 +190,12 @@
     display: block;
   }
 
+  .level-slide-marker {
+    top: calc(100% - var(--avn-slide-marker-position));
+    height: auto;
+    width: 100%;
+    left: 0%;
+  }
 
   .image-container {
     flex-direction: column;