[Split #88320] PR 8 - Add inverted-wheel handler for InvertedFlashList

[rlinoz]

Goal: Port RN-Web inverted wheel behavior into InvertedFlashList.

Scope:

• Add useInvertedWheelHandler.ts native no-op
• Add useInvertedWheelHandler.web.ts
• Update InvertedFlashList/index.tsx
• Update FlashList/index.tsx
• Add unit coverage for web and native behavior

Risk: Low-medium. QA web wheel scrolling across inverted surfaces.

Depends on: #89768

Parent issue: #88320
Source plan: #88320 (comment)

Issue Owner

Current Issue Owner: @DylanDylann