refactor: move renderer-dependent utils into workbench scope (#6621)

This PR cleans up the base-layer utilities so they no longer pull
renderer or workbench code. The renderer-only `isPrimitiveNode` guard
now lives in `src/renderer/utils/nodeTypeGuards.ts`, and the node
help/model/ordering helpers have moved into `src/workbench/utils`. All
affected services, stores, scripts, and tests were updated to import
from the new locations.

The idea is to reduce the number of Base→Renderer/Base→Workbench edges
(higher scoped base/common utils should not import from
renderer/workbench layers).

┆Issue is synchronized with this [Notion
page](https://www.notion.so/PR-6621-refactor-move-renderer-dependent-utils-into-workbench-scope-2a36d73d36508167aff0fc8a22202d7f)
by [Unito](https://www.unito.io)

tests-ui/tests/litegraph/core/LGraphNode.widgetOrder.test.ts

@@ -2,7 +2,7 @@ import { beforeEach, describe, expect, it } from 'vitest'
 
 import { LGraphNode } from '@/lib/litegraph/src/litegraph'
 import type { ISerialisedNode } from '@/lib/litegraph/src/types/serialisation'
-import { sortWidgetValuesByInputOrder } from '@/utils/nodeDefOrderingUtil'
+import { sortWidgetValuesByInputOrder } from '@/workbench/utils/nodeDefOrderingUtil'
 
 describe('LGraphNode widget ordering', () => {
   let node: LGraphNode

tests-ui/tests/utils/nodeDefOrderingUtil.test.ts

@@ -5,7 +5,7 @@ import { ComfyNodeDefImpl } from '@/stores/nodeDefStore'
 import {
   getOrderedInputSpecs,
   sortWidgetValuesByInputOrder
-} from '@/utils/nodeDefOrderingUtil'
+} from '@/workbench/utils/nodeDefOrderingUtil'
 
 describe('nodeDefOrderingUtil', () => {
   describe('getOrderedInputSpecs', () => {

tests-ui/utils/modelMetadataUtil.test.ts

@@ -1,6 +1,6 @@
 import { describe, expect, it } from 'vitest'
 
-import { getSelectedModelsMetadata } from '@/utils/modelMetadataUtil'
+import { getSelectedModelsMetadata } from '@/workbench/utils/modelMetadataUtil'
 
 describe('modelMetadataUtil', () => {
   describe('filterModelsByCurrentSelection', () => {