Move route select/deselect handling from the daemon server into exported
routemanager methods (SelectRoutes, DeselectRoutes, SelectAllRoutes,
DeselectAllRoutes) so every consumer shares one implementation: v4/v6
exit-pair expansion, exit-node mutual exclusion, and selection triggering.
Previously the exit-node exclusivity lived only in the daemon's
SelectNetworks RPC, so the Android and iOS bindings could leave two exit
nodes selected until the next network map reconciliation. Both bindings
now call the shared manager methods and enforce exclusivity at toggle
time, matching the desktop behavior.
cc0ab3247d