evolve: move logic to complete interrupted orphan resolution to new fn
This patch moves logic which completes an interrupted orphan resolution to it's
own new function. We will defining such functions for completing
phase-divergence and content-divergence too.
evolve: write data to evolvestate in case on conflicts in phase-divergence
This patch makes phase-divergence resolution write data to evolvestate instead
of graftstate. The `evolve --continue` handling of phase-divergence is broken
which will be done in upcoming patches.