Gw/videovariantfixes (#53)

* A fix for issue https://github.com/owncast/owncast/issues/770
- merge CPU slider functionality into main video variant form
- move slider constants into contants file for consistency and to reduce clutter on variant form file

* disable other forms and add a notice about vieo passthrough enabling

* Prettified Code!

* Tweak message text

* Prettified Code!

Co-authored-by: gingervitis <gingervitis@users.noreply.github.com>
Co-authored-by: Gabe Kangas <gabek@real-ity.com>
Co-authored-by: gabek <gabek@users.noreply.github.com>

web/styles/config-video-variants.scss

@@ -15,6 +15,15 @@
   .description {
     margin-top: 0;
   }
+  .passthrough-warning {
+    text-align: center;
+    padding: 1em;
+    color: var(--ant-warning);
+    font-size: 0.88em;
+    font-weight: 500;
+    background-color: var(--black-50);
+    border-radius: var(--container-border-radius);
+  }
 
   .cpu-usage-container,
   .bitrate-container {
@@ -25,10 +34,17 @@
     margin-top: 1em;
 
     .resolution-module,
-    .video-passthroug-module {
+    .video-passthrough-module {
       min-height: 30em;
     }
   }
+  // make some things look disabled when passthrough is on
+  &.video-passthrough-enabled {
+    .form-module:not(.video-passthrough-module) {
+      opacity: 0.25;
+      cursor: not-allowed;
+    }
+  }
 }
 
 .variants-table {