refactor: reusable dialog management

apps/client/src/common/components/identify-overlay/IdentifyOverlay.module.scss

@@ -15,7 +15,7 @@
   display: grid;
   place-content: center;
   text-align: center;
-  z-index: 100;
+  z-index: $zindex-modal;
   cursor: pointer;
 }
 

apps/client/src/common/components/view-params-editor/ViewParamsEditor.module.scss

@@ -11,8 +11,8 @@
 .backdrop {
   position: fixed;
   inset: 0;
-  z-index: 10;
-  background-color: rgba(0, 0, 0, 0.7);
+  z-index: $zindex-backdrop;
+  background-color: $backdrop-color;
   transition: opacity 300ms cubic-bezier(0.45, 1.005, 0, 1.005);
 
   &[data-starting-style],
@@ -27,7 +27,7 @@
   top: 0;
   right: 0;
   bottom: 0;
-  z-index: 11;
+  z-index: $zindex-dialog;
 
   width: 40rem;
   height: 100vh;
@@ -70,7 +70,7 @@
 .body {
   flex: 1;
   padding-bottom: 10vh;
-  overflow-y: scroll;
+  overflow-y: auto;
 }
 
 .footer {