Refactor: Composable disentangling (#5695)

## Summary

Prerequisite refactor/cleanup to use a global store instead of having
nodes throw up events to a parent component that stores a reference to a
singleton service that itself bootstraps and synchronizes with a
separate service to maintain a partially reactive but not fully reactive
set of states that describe some but not all aspects of the nodes on
either the litegraph, the vue side, or both.

## Changes

- **What**: Refactoring, the behavior should not change.
- **Dependencies**: A type utility to help with Vue component props

## Review Focus

Is there something about the current structure that this could affect
that would not be caught by our tests or using the application?

┆Issue is synchronized with this [Notion
page](https://www.notion.so/PR-5695-Refactor-Composable-disentangling-2746d73d365081e6938ce656932f3e36)
by [Unito](https://www.unito.io)

src/renderer/core/canvas/canvasStore.ts

@@ -99,6 +99,16 @@ export const useCanvasStore = defineStore('canvas', () => {
   const currentGraph = shallowRef<LGraph | null>(null)
   const isInSubgraph = ref(false)
 
+  // Provide selection state to all Vue nodes
+  const selectedNodeIds = computed(
+    () =>
+      new Set(
+        selectedItems.value
+          .filter((item) => item.id !== undefined)
+          .map((item) => String(item.id))
+      )
+  )
+
   whenever(
     () => canvas.value,
     (newCanvas) => {
@@ -122,6 +132,7 @@ export const useCanvasStore = defineStore('canvas', () => {
   return {
     canvas,
     selectedItems,
+    selectedNodeIds,
     nodeSelected,
     groupSelected,
     rerouteSelected,

src/renderer/core/canvas/injectionKeys.ts

@@ -2,13 +2,6 @@ import type { InjectionKey, Ref } from 'vue'
 
 import type { NodeProgressState } from '@/schemas/apiSchema'
 
-/**
- * Injection key for providing selected node IDs to Vue node components.
- * Contains a reactive Set of selected node IDs (as strings).
- */
-export const SelectedNodeIdsKey: InjectionKey<Ref<Set<string>>> =
-  Symbol('selectedNodeIds')
-
 /**
  * Injection key for providing executing node IDs to Vue node components.
  * Contains a reactive Set of currently executing node IDs (as strings).