Add view navigation history with back/forward stacks (bound to < and >).
Introduce CategoryKind enum to distinguish regular categories from
virtual ones (_Index, _Dim) that are synthesized at query time.
Add DrillIntoCell command that creates a drill view showing raw data
for an aggregated cell, expanding categories on Axis::None into Row
and Column axes while filtering by the cell's fixed coordinates.
Virtual categories default to Axis::None and are automatically added
to all views when the model is initialized.
Co-Authored-By: fiddlerwoaroof/git-smart-commit (unsloth/Qwen3.5-35B-A3B-GGUF:Q5_K_M)
Categories on the None axis are excluded from the grid and cell keys.
When evaluating cells, values across hidden dimensions are aggregated
using a per-measure function (default SUM). Adds evaluate_aggregated
to Model, none_cats to GridLayout, and 'n' shortcut in TileSelect.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
