Road to No explicit any: Group 8 (part 7) test files (#8459)

## Summary

This PR removes unsafe type assertions ("as unknown as Type") from test
files and improves type safety across the codebase.

### Key Changes

#### Type Safety Improvements
- Removed improper `as unknown as Type` patterns from 17 test files in
Group 8 part 7
- Replaced with proper TypeScript patterns using factory functions and
Mock types
- Fixed createTestingPinia usage in test files (was incorrectly using
createPinia)
- Fixed vi.hoisted pattern for mockSetDirty in viewport tests  
- Fixed vi.doMock lint issues with vi.mock and vi.hoisted pattern
- Retained necessary `as unknown as` casts only for complex mock objects
where direct type assertions would fail

### Files Changed

Test files (Group 8 part 7 - services, stores, utils):
- src/services/nodeOrganizationService.test.ts
- src/services/providers/algoliaSearchProvider.test.ts
- src/services/providers/registrySearchProvider.test.ts
- src/stores/comfyRegistryStore.test.ts
- src/stores/domWidgetStore.test.ts
- src/stores/executionStore.test.ts
- src/stores/firebaseAuthStore.test.ts
- src/stores/modelToNodeStore.test.ts
- src/stores/queueStore.test.ts
- src/stores/subgraphNavigationStore.test.ts
- src/stores/subgraphNavigationStore.viewport.test.ts
- src/stores/subgraphStore.test.ts
- src/stores/systemStatsStore.test.ts
- src/stores/workspace/nodeHelpStore.test.ts
- src/utils/colorUtil.test.ts
- src/utils/executableGroupNodeChildDTO.test.ts

Source files:
- src/stores/modelStore.ts - Improved type handling

### Testing
- All TypeScript type checking passes (`pnpm typecheck`)
- All affected test files pass (`pnpm test:unit`)
- Linting passes without errors (`pnpm lint`)
- Code formatting applied (`pnpm format`)

Part of the "Road to No Explicit Any" initiative, cleaning up type
casting issues from branch `fix/remove-any-types-part8`.

### Previous PRs in this series:
- Part 2: #7401
- Part 3: #7935
- Part 4: #7970
- Part 5: #8064
- Part 6: #8083
- Part 7: #8092
- Part 8 Group 1: #8253
- Part 8 Group 2: #8258
- Part 8 Group 3: #8304
- Part 8 Group 4: #8314
- Part 8 Group 5: #8329
- Part 8 Group 6: #8344
- Part 8 Group 7: #8459 (this PR)

┆Issue is synchronized with this [Notion
page](https://www.notion.so/PR-8459-Road-to-No-explicit-any-Group-8-part-7-test-files-2f86d73d36508114ad28d82e72a3a5e9)
by [Unito](https://www.unito.io)

src/stores/subgraphStore.test.ts

@@ -1,9 +1,9 @@
-import { createTestingPinia } from '@pinia/testing'
 import { setActivePinia } from 'pinia'
 import { beforeEach, describe, expect, it, vi } from 'vitest'
 
 import type { ComfyNodeDef as ComfyNodeDefV1 } from '@/schemas/nodeDefSchema'
 import type { GlobalSubgraphData } from '@/scripts/api'
+import type { ExportedSubgraph } from '@/lib/litegraph/src/types/serialisation'
 import { api } from '@/scripts/api'
 import { app as comfyApp } from '@/scripts/app'
 import { useLitegraphService } from '@/services/litegraphService'
@@ -14,6 +14,7 @@ import {
   createTestSubgraph,
   createTestSubgraphNode
 } from '@/lib/litegraph/src/subgraph/__fixtures__/subgraphHelpers'
+import { createTestingPinia } from '@pinia/testing'
 
 // Mock telemetry to break circular dependency (telemetry → workflowStore → app → telemetry)
 vi.mock('@/platform/telemetry', () => ({
@@ -96,10 +97,18 @@ describe('useSubgraphStore', () => {
     const graph = subgraphNode.graph
     graph.add(subgraphNode)
     vi.mocked(comfyApp.canvas).selectedItems = new Set([subgraphNode])
-    vi.mocked(comfyApp.canvas)._serializeItems = vi.fn(() => ({
-      nodes: [subgraphNode.serialize()],
-      subgraphs: [subgraph.serialize() as any]
-    }))
+    vi.mocked(comfyApp.canvas)._serializeItems = vi.fn(() => {
+      const serializedSubgraph = {
+        ...subgraph.serialize(),
+        links: [],
+        groups: [],
+        version: 1
+      } as Partial<ExportedSubgraph> as ExportedSubgraph
+      return {
+        nodes: [subgraphNode.serialize()],
+        subgraphs: [serializedSubgraph]
+      }
+    })
     //mock saving of file
     vi.mocked(api.storeUserData).mockResolvedValue({
       status: 200,