Norma #6: Abstract to library level
- Tab navigation with wrap now in library, not application
- AdvancedTableState.tabToNextCell/tabToPrevCell for in-memory data
- VirtualAdvancedTableState.tabToNextCell/tabToPrevCell for paginated data
- DRY: same logic available in both table widgets
- Tab/Shift+Tab with wrap navigation in editing mode
- tab_out/tab_shift result fields for application handling
- Cursor position, blinking, background color fixes
- markRowSaved() to clear dirty state after save
- last_edited_row only set when actual changes made
- New module: table_core.zig with common table rendering logic
- drawCellActiveIndicator(): visual indicator for selected cell
- detectDoubleClick(): timing-based double-click detection
- handleEditingKeyboard(): common keyboard handling for editing
- blendColor(), startsWithIgnoreCase(): utilities
VirtualAdvancedTable now uses table_core:
- Active cell indicator in drawRows (visible highlight on selected cell)
- Double-click detection in handleMouseClick
- Added state fields: last_click_time, last_click_row, last_click_col
AdvancedTable changes:
- Improved cell active indicator (alpha 0.35, double border)
- Added double-click fields to state
- Space starts editing with empty value
- Alphanumeric keys start editing in editable cells
