rework minimap, toolbox, and menu designs with unified theming (#6038)

## Summary

This PR redesigns the graph canvas interface components including
minimap, toolbox, and menu systems with updated spacing, colors, and
interaction patterns - using the design tokens directly from Figma,
which can be used elsewhere going forward.

There are some other changes to the designs, outlined
[here](https://www.notion.so/comfy-org/Update-Minimap-Menu-v2-2886d73d365080e88e12f8df027019c0):

- [x]  Update/standardize the padding between viewport and toolbox
- [x] Update toolbox component’s style to match the other floating menus
style (border radius, height, padding and follow theme colors)
- [x]  Expose the minimap button
- [x]  Remove the focus button and delete it’s keybinding
- [x]  Group the hand and the default cursor buttons


https://github.com/user-attachments/assets/92542e60-c32d-4a21-a6f6-e72837a70b17

## Review Focus

New CSS variables for cross-component theming consistency and
CanvasModeSelector component extraction for improved code organization.

┆Issue is synchronized with this [Notion
page](https://www.notion.so/PR-6038-rework-minimap-toolbox-and-menu-designs-with-unified-theming-28b6d73d36508191a0c6cf8036d965c4)
by [Unito](https://www.unito.io)

---------

Co-authored-by: github-actions <github-actions@github.com>

src/components/graph/selectionToolbox/SubmenuPopover.vue

@@ -56,13 +56,6 @@ import { useNodeCustomization } from '@/composables/graph/useNodeCustomization'
 
 interface Props {
   option: MenuOption
-  containerStyles: {
-    width: string
-    height: string
-    backgroundColor: string
-    border: string
-    borderRadius: string
-  }
 }
 
 interface Emits {
@@ -117,11 +110,9 @@ const submenuPt = computed(() => ({
   content: {
     class: [
       'text-neutral dark-theme:text-white rounded-lg',
-      'shadow-lg border border-zinc-200 dark-theme:border-zinc-700'
-    ],
-    style: {
-      backgroundColor: props.containerStyles.backgroundColor
-    }
+      'shadow-lg border border-zinc-200 dark-theme:border-zinc-700',
+      'bg-interface-panel-surface'
+    ]
   }
 }))
 </script>