Implement nested cell type selection in heatmap tab #49
Description
(Based on discussions from issue #21 that has been closed.)
I want to implement more granular cell type selection, perhaps using the original, more detailed Cell type and Cell class columns. If possible, I would like the user to be able to select them in a nested fashion, where selecting a general cell type (e.g. Neurons) will select all of the cell types that are categorized within it (e.g. cell class Excitatory neurons and cell type Cortical excitatory neurons).
I may be able to achieve my goal of nested checkboxes using the shinytree package, as used in the example here.
I will need to update input validation once I implement this, to show an error message only if less than two cell clusters are selected.