Excludes the mm bookmark so the in-progress merge target stays put.

Assisted-by: Claude Opus 4.7 via Claude Code

diff --git a/.config/jj/config.toml b/.config/jj/config.toml
index 9d1124d2..f51389d1 100644
--- a/.config/jj/config.toml
+++ b/.config/jj/config.toml
@@ -102,6 +102,7 @@ edit = true
 [aliases]
 accuse = ["file", "annotate"]
 jj = []
+sweep = ["abandon", "--revisions", 'trunk():: & empty() & ~bookmarks(exact:"mm")']
 tug = ["util", "exec", "--", "bash", "-c", """
   ref=${1:-@}
   jj bookmark move --from "closest_bookmark($ref)" --to "closest_pushable($ref)"