v0.1.3

First release under the new gem name mark-twin (previously grubber-twin).

Fixes:

• Stage-1 picker could return the wrong program when names repeat across sync-files or are substrings of each other (Git/GitHub)
• Conflict detection now uses the same 60s tolerance as the status display — no more spurious conflict warnings from mtime jitter
• A failing post-sync Cmd is now reported instead of silently succeeding
• Preview mapfile cleanup, shell-escaped apex config values