test: migrate as unknown as to @total-typescript/shoehorn (#10761)

*PR Created by the Glary-Bot Agent*

---

## Summary

- Replace all `as unknown as Type` assertions in 59 unit test files with
type-safe `@total-typescript/shoehorn` functions
- Use `fromPartial<Type>()` for partial mock objects where deep-partial
type-checks (21 files)
- Use `fromAny<Type>()` for fundamentally incompatible types: null,
undefined, primitives, variables, class expressions, and mocks with
test-specific extra properties that `PartialDeepObject` rejects
(remaining files)
- All explicit type parameters preserved so TypeScript return types are
correct
- Browser test `.spec.ts` files excluded (shoehorn unavailable in
`page.evaluate` browser context)

## Verification

- `pnpm typecheck` ✅
- `pnpm lint` ✅
- `pnpm format` ✅
- Pre-commit hooks passed (format + oxlint + eslint + typecheck)
- Migrated test files verified passing (ran representative subset)
- No test behavior changes — only type assertion syntax changed
- No UI changes — screenshots not applicable

┆Issue is synchronized with this [Notion
page](https://www.notion.so/PR-10761-test-migrate-as-unknown-as-to-total-typescript-shoehorn-3336d73d365081f6b8adc44db5dcc380)
by [Unito](https://www.unito.io)

---------

Co-authored-by: Glary-Bot <glary-bot@users.noreply.github.com>
Co-authored-by: Amp <amp@ampcode.com>

src/components/graph/widgets/domWidgetZIndex.test.ts

@@ -1,7 +1,7 @@
+import { fromAny } from '@total-typescript/shoehorn'
 import { describe, expect, it } from 'vitest'
 
 import { LGraph, LGraphNode } from '@/lib/litegraph/src/litegraph'
-
 import { getDomWidgetZIndex } from './domWidgetZIndex'
 
 describe('getDomWidgetZIndex', () => {
@@ -15,7 +15,7 @@ describe('getDomWidgetZIndex', () => {
     first.order = 0
     second.order = 1
 
-    const nodes = (graph as unknown as { _nodes: LGraphNode[] })._nodes
+    const nodes = fromAny<{ _nodes: LGraphNode[] }, unknown>(graph)._nodes
     nodes.splice(nodes.indexOf(first), 1)
     nodes.push(first)