Fix Skani: increase disk allocation and delete archive after extraction

35 GB archive + 56 GB extracted simultaneously exhausted the ~92 GB disk
(2x multiplier was too tight). Bump to 3x and rm the archive immediately
after extraction to free 35 GB before skani search runs.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: tpshea2

wdl/tasks/MAG/Skani.wdl

@@ -32,7 +32,7 @@ task Skani {
         RuntimeAttr? runtime_attr_override
     }
 
-    Int disk_size = 20 + ceil(2.0 * size(skani_db_tgz, "GB")) + ceil(2.0 * size(bins, "GB"))
+    Int disk_size = 20 + ceil(3.0 * size(skani_db_tgz, "GB")) + ceil(2.0 * size(bins, "GB"))
 
     command <<<
         set -euxo pipefail
@@ -46,6 +46,8 @@ task Skani {
         else
             tar -xzf ~{skani_db_tgz} -C skani_db
         fi
+        # Free the 35 GB archive — no longer needed once extracted
+        rm -f ~{skani_db_tgz}
 
         # Stage bins to a local directory so we can glob them
         mkdir -p bins_dir