test: audit skipped tests — prune stale, re-enable stable, remove dead code (#10312)

## Summary

Audit all skipped/fixme tests: delete stale tests whose underlying
features were removed, re-enable tests that pass with minimal fixes, and
remove orphaned production code that only the deleted tests exercised.
Net result: **−2,350 lines** across 50 files.

## Changes

- **Pruned stale skipped tests** (entire files deleted):
- `LGraph.configure.test.ts`, `LGraph.constructor.test.ts` — tested
removed LGraph constructor paths
- `LGraphCanvas.ghostAutoPan.test.ts`,
`LGraphCanvas.linkDragAutoPan.test.ts`, `useAutoPan.test.ts`,
`useSlotLinkInteraction.autoPan.test.ts` — tested removed auto-pan
feature
- `useNodePointerInteractions.test.ts` — single skipped test for removed
callback
  - `ImageLightbox.test.ts` — component replaced by `MediaLightbox`
- `appModeWidgetRename.spec.ts` (E2E) — feature removed; helper
`AppModeHelper.ts` also deleted
- `domWidget.spec.ts`, `widget.spec.ts` (E2E) — tested removed widget
behavior

- **Removed orphaned production code** surfaced by test pruning:
- `useAutoPan.ts` — composable + 93 lines of auto-pan logic in
`LGraphCanvas.ts`
  - `ImageLightbox.vue` — replaced by `MediaLightbox`
- Auto-pan integration in `useSlotLinkInteraction.ts` and
`useNodeDrag.ts`
- Dead settings (`LinkSnapping.AutoPanSpeed`,
`LinkSnapping.AutoPanMargin`) in `coreSettings.ts` and
`useLitegraphSettings.ts`
- Unused subgraph methods (`SubgraphNode.getExposedInput`,
`SubgraphInput.getParentInput`)
- Dead i18n key, dead API schema field, dead fixture exports
(`dirtyTest`, `basicSerialisableGraph`)
  - Dead test utility `litegraphTestUtils.ts`

- **Re-enabled skipped tests with minimal fixes**:
  - `useBrowserTabTitle.test.ts` — removed skip, test passes as-is
- `eventUtils.test.ts` — replaced MSW dependency with direct `fetch`
mock
- `SubscriptionPanel.test.ts` — stabilized button selectors,
timezone-safe date assertion
- `LinkConnector.test.ts` — removed stale describe blocks, kept passing
suite
- `widgetUtil.test.ts` — removed skipped tests for deleted functionality
- `comfyManagerStore.test.ts` — removed skipped `isPackInstalling` /
`action buttons` / `loading states` blocks

- **Re-enabled then re-skipped 3 flaky E2E tests** (fail in CI for
pre-existing reasons):
- `browserTabTitle.spec.ts` — canvas click timeout (element not visible)
  - `groupNode.spec.ts` — screenshot diff (stale golden image)
  - `nodeSearchBox.spec.ts` — `p-dialog-mask` intercepts pointer events

- **Simplified production code** alongside test cleanup:
- `useNodeDrag.ts` — removed auto-pan integration, simplified from
170→100 lines
- `DropZone.vue` — refactored URL-drop handling, removed unused code
path
- `ToInputFromIoNodeLink.ts`, `SubgraphInputEventMap.ts` — removed dead
subgraph wiring

- **Dependencies**: none
- **Breaking**: none (all removed code was internal/unused)

## Review Focus

- Confirm deleted production code (`useAutoPan`, `ImageLightbox`,
subgraph methods) has no remaining callers
- Validate that simplified `useNodeDrag.ts` preserves drag behavior
without auto-pan
- Check that re-skipped E2E tests have clear skip reasons for future
triage

## Screenshots (if applicable)

N/A

---------

Co-authored-by: Amp <amp@ampcode.com>
Co-authored-by: github-actions <github-actions@github.com>

src/renderer/extensions/vueNodes/composables/useNodePointerInteractions.test.ts

@@ -157,31 +157,6 @@ describe('useNodePointerInteractions', () => {
     expect(startDrag).toHaveBeenCalledWith(leftClickEvent, 'test-node-123')
   })
 
-  it.skip('should call onNodeSelect on pointer down', async () => {
-    const { handleNodeSelect } = useNodeEventHandlers()
-
-    const { pointerHandlers } = useNodePointerInteractions('test-node-123')
-
-    // Selection should happen on pointer down
-    const downEvent = createPointerEvent('pointerdown', {
-      clientX: 100,
-      clientY: 100
-    })
-    pointerHandlers.onPointerdown(downEvent)
-
-    expect(handleNodeSelect).toHaveBeenCalledWith(downEvent, 'test-node-123')
-
-    vi.mocked(handleNodeSelect).mockClear()
-
-    // Even if we drag, selection already happened on pointer down
-    pointerHandlers.onPointerup(
-      createPointerEvent('pointerup', { clientX: 200, clientY: 200 })
-    )
-
-    // onNodeSelect should not be called again on pointer up
-    expect(handleNodeSelect).not.toHaveBeenCalled()
-  })
-
   it('should handle drag termination via cancel and context menu', async () => {
     const { handleNodeSelect } = useNodeEventHandlers()