merge: use labels in prompts to the user Now that we persist the labels, we can consistently use the labels in prompts for the user without risk of confusion. This changes a huge amount of command output: This means that merge prompts like: no tool found to merge a keep (l)ocal, take (o)ther, or leave (u)nresolved? u and remote changed a which local deleted use (c)hanged version, leave (d)eleted, or leave (u)nresolved? c become: no tool found to merge a keep (l)ocal [working copy], take (o)ther [destination], or leave (u)nresolved? u and remote [source] changed a which local [dest] deleted use (c)hanged version, leave (d)eleted, or leave (u)nresolved? c where "working copy" and "destination" were supplied by the command that requested the merge as labels for conflict markers, and thus should be human-friendly.