fix: handle scroll frozen columns width

[fangsmile]

Summary

• fix body layout positioning when scrollFrozenCols limits frozen columns by maxFrozenWidth
• keep body horizontal scrollbar hidden when all body columns fit while preserving frozen-area scrolling
• add an issue 5187 debug demo and regression coverage

Tests

• npx jest tests/options/listTable-scroll-frozen-cols.test.ts --runInBand
• npm run compile

Fixes #5187