Road to No explicit any: Group 8 (part 6) test files (#8344)

## 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 all instances of "as unknown as" patterns from test files
- Used proper factory functions from litegraphTestUtils instead of
custom mocks
- Made incomplete mocks explicit using Partial<T> types
- Fixed DialogStore mocking with proper interface exports
- Improved type safety with satisfies operator where applicable

#### App Parameter Removal
- **Removed the unused `app` parameter from all ComfyExtension interface
methods**
- The app parameter was always undefined at runtime as it was never
passed from invokeExtensions
- Affected methods: init, setup, addCustomNodeDefs,
beforeRegisterNodeDef, beforeRegisterVueAppNodeDefs,
registerCustomNodes, loadedGraphNode, nodeCreated, beforeConfigureGraph,
afterConfigureGraph

##### Breaking Change Analysis
Verified via Sourcegraph that this is NOT a breaking change:
- Searched all 10 affected methods across GitHub repositories
- Only one external repository
([drawthingsai/draw-things-comfyui](https://github.com/drawthingsai/draw-things-comfyui))
declares the app parameter in their extension methods
- That repository never actually uses the app parameter (just declares
it in the function signature)
- All other repositories already omit the app parameter
- Search queries used:
- [init method
search](https://sourcegraph.com/search?q=context:global+repo:%5Egithub%5C.com/.*+lang:typescript+%22init%28app%22+-repo:Comfy-Org/ComfyUI_frontend&patternType=standard)
- [setup method
search](https://sourcegraph.com/search?q=context:global+repo:%5Egithub%5C.com/.*+lang:typescript+%22setup%28app%22+-repo:Comfy-Org/ComfyUI_frontend&patternType=standard)
  - Similar searches for all 10 methods confirmed no usage

### Files Changed

Test files:
-
src/components/settings/widgets/__tests__/WidgetInputNumberInput.test.ts
- src/services/keybindingService.escape.test.ts  
- src/services/keybindingService.forwarding.test.ts
- src/utils/__tests__/newUserService.test.ts →
src/utils/__tests__/useNewUserService.test.ts
- src/services/jobOutputCache.test.ts
-
src/renderer/extensions/vueNodes/widgets/composables/useRemoteWidget.test.ts
-
src/renderer/extensions/vueNodes/widgets/composables/useIntWidget.test.ts
-
src/renderer/extensions/vueNodes/widgets/composables/useFloatWidget.test.ts

Source files:
- src/types/comfy.ts - Removed app parameter from ComfyExtension
interface
- src/services/extensionService.ts - Improved type safety with
FunctionPropertyNames helper
- src/scripts/metadata/isobmff.ts - Fixed extractJson return type per
review
- src/extensions/core/*.ts - Updated extension implementations
- src/scripts/app.ts - Updated app initialization

### Testing
- All existing tests pass
- Type checking passes  
- ESLint/oxlint checks pass
- No breaking changes for external repositories

Part of the "Road to No Explicit Any" initiative.

### 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 (this PR)

src/renderer/extensions/vueNodes/widgets/components/WidgetGalleria.test.ts

@@ -290,7 +290,7 @@ describe('WidgetGalleria Image Display', () => {
       await galleria.vm.$emit('update:activeIndex', 2)
 
       // Check that the internal activeIndex ref was updated
-      const vm = wrapper.vm as any
+      const vm = wrapper.vm as typeof wrapper.vm & { activeIndex: number }
       expect(vm.activeIndex).toBe(2)
     })
   })

src/renderer/extensions/vueNodes/widgets/components/WidgetInputNumberInput.test.ts

@@ -197,13 +197,12 @@ describe('WidgetInputNumberInput Large Integer Precision Handling', () => {
 describe('WidgetInputNumberInput Edge Cases for Precision Handling', () => {
   it('handles null/undefined model values gracefully', () => {
     const widget = createMockWidget(0, 'int')
-    // Mount with undefined as modelValue
     const wrapper = mount(WidgetInputNumberInput, {
       global: { plugins: [i18n] },
       props: {
         widget,
-        modelValue: undefined as any
-      }
+        modelValue: undefined
+      } as { widget: SimplifiedWidget<number>; modelValue: number | undefined }
     })
 
     expect(wrapper.findAll('button').length).toBe(2)

src/renderer/extensions/vueNodes/widgets/components/form/FormSelectButton.test.ts

@@ -8,7 +8,7 @@ describe('FormSelectButton Core Component', () => {
   // Type-safe helper for mounting component
   const mountComponent = (
     modelValue: string | null | undefined = null,
-    options: (string | number | Record<string, any>)[] = [],
+    options: unknown[] = [],
     props: Record<string, unknown> = {}
   ) => {
     return mount(FormSelectButton, {
@@ -17,7 +17,11 @@ describe('FormSelectButton Core Component', () => {
       },
       props: {
         modelValue,
-        options: options as any,
+        options: options as (
+          | string
+          | number
+          | { label: string; value: string | number }
+        )[],
         ...props
       }
     })
@@ -474,7 +478,7 @@ describe('FormSelectButton Core Component', () => {
     })
 
     it('handles mixed type options safely', () => {
-      const mixedOptions: any[] = [
+      const mixedOptions: unknown[] = [
         'string',
         123,
         { label: 'Object', value: 'obj' }