update minimap and canvas bg to use menu color tokens (#6589)

Update minimap and graph canvas menu (bottom right) to use menu tokens.
Change canvas BG color on default dark theme.

<img width="3840" height="2029" alt="image"
src="https://github.com/user-attachments/assets/6d168981-df27-40c0-829c-59150b8a6a12"
/>


┆Issue is synchronized with this [Notion
page](https://www.notion.so/PR-6589-wip-Style-graph-canvas-color-2a26d73d365081cb88c4c4bdb2b6d3a5)
by [Unito](https://www.unito.io)

---------

Co-authored-by: github-actions <github-actions@github.com>
Co-authored-by: Alexander Brown <drjkl@comfy.org>

src/components/graph/CanvasModeSelector.vue

@@ -2,14 +2,14 @@
   <Button
     ref="buttonRef"
     severity="secondary"
-    class="group h-8 rounded-none! bg-interface-panel-surface p-0 transition-none! hover:rounded-lg! hover:bg-button-hover-surface!"
+    class="group h-8 rounded-none! bg-comfy-menu-bg p-0 transition-none! hover:rounded-lg! hover:bg-interface-button-hover-surface!"
     :style="buttonStyles"
     @click="toggle"
   >
     <template #default>
       <div class="flex items-center gap-1 pr-0.5">
         <div
-          class="rounded-lg bg-button-active-surface p-2 group-hover:bg-button-hover-surface"
+          class="rounded-lg bg-interface-panel-selected-surface p-2 group-hover:bg-interface-button-hover-surface"
         >
           <i :class="currentModeIcon" class="block h-4 w-4" />
         </div>
@@ -114,7 +114,7 @@ const popoverPt = computed(() => ({
   content: {
     class: [
       'mb-2 text-text-primary',
-      'shadow-lg border border-node-border',
+      'shadow-lg border border-interface-stroke',
       'bg-nav-background',
       'rounded-lg',
       'p-2 px-3',