coverage85-step2d: 新测试 lint 清理（删无用导入与变量）

tests/test_host_coverage85_2.py

@@ -29,10 +29,8 @@ sys.path.insert(0, str(REPO_ROOT))
 
 import host
 from host import (
-    Server,
     dispatch,
     dispatch_from_branch,
-    make_worktree,
     merge_task,
     notify_failure,
     run_goal_loop,