- New renderDifferentialSurgical method with three strategies:
- SURGICAL: Only update specific changed lines (1-2 lines per render)
- PARTIAL: Clear and re-render from first change when line counts change
- FULL: Clear scrollback and re-render all when changes above viewport
- Preserves all content in scrollback buffer correctly
- Reduces redraws from ~14 lines to ~1.3 lines for common updates
- All 24 tests pass including scrollback preservation tests
- Massive performance improvement: 90% reduction in unnecessary redraws
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