[Maps] Saving the workspace with temporary layers saves them in temporary state

[kindsun]

If a user saves the workspace part-way through the map add process, while the layer is still temporary, the layer is saved and will be repopulated the next time the workspace is loaded. This can be clunky as the layer in temporary state was meant to be a transient state of layer adding. We should consider filtering out temporary layers on workspace save.

[elasticmachine]

Pinging @elastic/kibana-gis

[thomasneirynck]

Consider removing the concept of temporary layers and promotion altogether. The same can be achieved with the existing add-layer and remove-layer actions.

[nreese]

closed by #30542