d99d22820e
Three copies of cross_product existed (grid.rs, app.rs, persistence/mod.rs) with slightly different signatures. Extracted into GridLayout in src/view/layout.rs, which is now the single canonical mapping from a View to a 2-D grid: row/col counts, labels, and cell_key(row, col) → CellKey. All consumers updated to use GridLayout::new(model, view): - grid.rs: render_grid, total-row computation, page bar - persistence/mod.rs: export_csv - app.rs: move_selection, jump_to_last_row/col, scroll_rows, search_navigate, selected_cell_key Also includes two app.rs UI bug fixes that were discovered while refactoring: - Ctrl+Arrow tile movement was unreachable (shadowed by plain arrow arms); moved before plain arrow handlers - RemoveFormula dispatch now passes target_category (required by the formula management fix in the previous commit) GridLayout has 6 unit tests covering counts, label formatting, cell_key correctness, out-of-bounds, page coord inclusion, and evaluate round-trip. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>