optimize node change management
optimize node change management

- only trigger layoutactions if a node change occurred on an action node
- distribute all added nodes regardless of slot setting
-- moving a node also triggers a node change, avoid acting on these
--- this should also avoid trying to observe the same node twice

Signed-off-by: Patrik Kullman <8612fec4a6bb0a11ae3ca5e27ebb050b4a73b7ea@neovici.se>

Neovici/cosmoz-bottom-bar,Neovici/cosmoz-bottom-bar