style: fix spotless try/catch formatting in AddIndexExec

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: beinan

lance-spark-base_2.12/src/main/scala/org/apache/spark/sql/execution/datasources/v2/AddIndexExec.scala

@@ -99,13 +99,14 @@ case class AddIndexExec(
         "num_segments option is only supported for index types that use segmented builds (e.g., zonemap)")
     }
     val validatedNumSegments: Option[Int] = numSegmentsOpt.map { arg =>
-      val value = try {
-        arg.value.asInstanceOf[Number].intValue()
-      } catch {
-        case _: ClassCastException =>
-          throw new IllegalArgumentException(
-            s"num_segments must be a positive integer, got: ${arg.value}")
-      }
+      val value =
+        try {
+          arg.value.asInstanceOf[Number].intValue()
+        } catch {
+          case _: ClassCastException =>
+            throw new IllegalArgumentException(
+              s"num_segments must be a positive integer, got: ${arg.value}")
+        }
       if (value <= 0) {
         throw new IllegalArgumentException(
           s"num_segments must be a positive integer, got: $value")