Match Go delete_collection: skip volumes with compaction in progress

Go checks !v.isCompactionInProgress.Load() before destroying a volume
during collection deletion, skipping compacting volumes. Also changed
destroy errors to log instead of aborting the entire collection delete.

seaweed-volume/src/storage/disk_location.rs

@@ -392,7 +392,7 @@ impl DiskLocation {
         let vids: Vec<VolumeId> = self
             .volumes
             .iter()
-            .filter(|(_, v)| v.collection == collection)
+            .filter(|(_, v)| v.collection == collection && !v.is_compacting())
             .map(|(vid, _)| *vid)
             .collect();
 
@@ -401,7 +401,9 @@ impl DiskLocation {
                 crate::metrics::VOLUME_GAUGE
                     .with_label_values(&[&v.collection, "volume"])
                     .dec();
-                v.destroy(false)?;
+                if let Err(e) = v.destroy(false) {
+                    warn!(volume_id = vid.0, error = %e, "delete collection: failed to destroy volume");
+                }
             }
         }
 

seaweed-volume/src/storage/volume.rs

@@ -556,6 +556,11 @@ impl Volume {
         Ok(v)
     }
 
+    /// Returns true if the volume is currently being compacted.
+    pub fn is_compacting(&self) -> bool {
+        self.is_compacting
+    }
+
     // ---- File naming (matching Go) ----
 
     /// Base filename: dir/collection_id or dir/id