[Symbol] Improve the Symbol compartment placement on FreeFlowForm LayoutStrategy Nodes
When displaying a Symbol in a Node with the FreeFlowForm LayoutStrategy, the Symbol appears as a regular child in the body of the Node and will be mixed with other children:
It should instead be displayed in its own compartment at the bottom of the Node, similarly to the List LayoutStrategy Nodes:
Edited by Titouan Bouëte-Giraud