feat(iot-hub): polish connectivity card selected/idle states

- Selected card inverts the icon container: primary-coloured
  background with the masked glyph painted white, on top of the
  existing primary border + inset shadow.
- Default (idle, non-hovered) cards use a transparent border so the
  outline appears only on hover or when selected — the 1px layout
  space stays intact to avoid jitter.

ui-ngx/src/app/modules/home/components/iot-hub/device-install-dialog/device-install-dialog.component.scss

@@ -115,7 +115,7 @@
     padding: 16px;
     height: 116px;
     background: rgba($tb-primary-color, 0.04);
-    border: 1px solid rgba(0, 0, 0, 0.12);
+    border: 1px solid transparent;
     border-radius: 6px;
     cursor: pointer;
     text-align: left;
@@ -128,6 +128,16 @@
 
     &.selected {
       box-shadow: 0 0 0 1px $tb-primary-color inset;
+
+      // Selected state inverts the icon: primary-coloured container
+      // with the masked glyph painted in white.
+      .tb-connectivity-card-icon {
+        background: $tb-primary-color;
+      }
+
+      .tb-connectivity-card-icon-mask {
+        background-color: white;
+      }
     }
   }