Add ability to edit past operations in feature tree by double-clicking them in feature tree

[franknoirot]

Though we have point-and-click flows for some modeling operations like extrude and fillet, after they are added users are left to edit the output KCL code directly if they wish to make any changes to the operation after the fact. We should support the ability to edit these parameters using the same GUI command bar flow as when they perform the original oepration.

Engine notes

None, requires no engine intervention

API/KCL notes

None, requires no new KCL representations

Point-and-click notes

1. User will double-click or right-click menu to edit
2. Need to be able to re-invoke command bar with previously-entered values
3. Need to re-select the selected items when revisiting the selection argument
4. Instead of adding to code, this command flow will edit an AST node's arguments.
5. Future work: better review view in the command bar