Row Selection and Cell Selection

[jameskerr]

The table view and the inspector lack the ability to select rows and columns.

Add this feature back. With the ability to select certain cells.

There should also be a menu shown when right-clicking on selected cells to allow operations on all highlighted cells.

And we'll want to adjust the context menu depending on the selection.

The behavior in Google Workspace tools (Sheets, Docs, etc.) has been cited as a model for ideal selection behavior since it should be familiar to most users.