heal: Better reporting to mc with dangling/timeout errors (#20690)

The code assigns corrupted state to a drive for any unexpected error,
which is confusing for users. This change will make sure to assign
corrupted state only for corrupted parts or xl.meta. Use unknown state
with a explanation for any unexpected error, like canceled, deadline
errors, drive timeout, ...

Also make sure to return the bucket/object name when the object is not
found or marked not found by the heal dangling code.

cmd/erasure-server-pool.go

@@ -2593,15 +2593,22 @@ func (z *erasureServerPools) HealObject(ctx context.Context, bucket, object, ver
 		}
 	}
 
+	hr := madmin.HealResultItem{
+		Type:      madmin.HealItemObject,
+		Bucket:    bucket,
+		Object:    object,
+		VersionID: versionID,
+	}
+
 	// At this stage, all errors are 'not found'
 	if versionID != "" {
-		return madmin.HealResultItem{}, VersionNotFound{
+		return hr, VersionNotFound{
 			Bucket:    bucket,
 			Object:    object,
 			VersionID: versionID,
 		}
 	}
-	return madmin.HealResultItem{}, ObjectNotFound{
+	return hr, ObjectNotFound{
 		Bucket: bucket,
 		Object: object,
 	}