Use CNV distributions to identify additional Ewings tumor cells

> In looking at this I am kind of curious what cell types are in the first hump in the bimodal distribution that we see in the unknown cells are for 822 and 824 when using endo-immune or immune. Using endo + immune together it looks like we might be able to pull out two groups of unknown and could actually label some of the unknown as tumor cells. That's a question for another time, but it might be pretty easy to just plot the total CNV distributions by cell type for that group and see what it looks like.

_Originally posted by @allyhawkins in https://github.com/AlexsLemonade/OpenScPCA-analysis/pull/1144#pullrequestreview-2893220384_

---

The goal of this issue is to explore whether we can use inferCNV results for Ewings samples to identify additional tumor cells that were not identified in the `cell-type-ewings` module.

Start by reviewing the inferCNV results and the cell-type-ewings module for Ewings samples 822 and 824. Plot total CNV distributions by cell type for the unknown cells, comparing the endo-immune or immune groups with endo plus immune. Done means determining whether the distributions support identifying and labeling additional tumor cells.

Written by the indexing model from the issue text.