🐛Bug Fixes And List Virtualization (#253)

The named version selector now has a virtualized list of entries. This
prevents massive upfront loading.
Pr also fixes the following issues :

-  #252
-  #251
-  iTwin/changed-elements#251

Author: CalebGerman

.changeset/crazy-singers-hope.md

@@ -0,0 +1,12 @@
+---
+"@itwin/changed-elements-react": minor
+---
+
+_Frontend Enhancements:_
+
+1. Change named version list to be a infinite list, so we do not spam the UI with quires for constructing Named Versions
+
+_Frontend Bug Fixes:_
+
+1. Fixed active version header not clearing once a comparison is complete
+2. Disabled process result buttons when a comparison is currently being run

packages/changed-elements-react/src/NamedVersionSelector/NamedVersionSelector.scss

@@ -111,7 +111,8 @@
 
       display: grid;
       grid: 1fr / minmax(min-content, 1fr) minmax(min-content, auto) minmax(min-content, auto);
-      column-gap: var(--iui-size-m);
+      height: 100%;
+      width: 100%;
 
       > * {
         padding-inline: var(--_cer_v1_container-margin-internal);
@@ -164,5 +165,15 @@
     ._cer_v1_not-processed {
       color: var(--iui-color-border);
     }
+
+    ._cer_v1_version-content {
+      flex: 1;
+      min-width: 0;
+    }
+
+    ._cer_v1_version-details {
+      display: grid;
+      gap: 1px;
+    }
   }
 }