[AMORO-4186] Add support for Parquet row-group merging in IcebergRewriteExecutor (#4188)

* Add support for Parquet row-group merging in IcebergRewriteExecutor

* Enhance Parquet row-group merge support for Iceberg V2 tables and add version checks

* Add cleanup for orphaned merged output files in Parquet row-group merge

* Refactor ParquetFileMergeRunner to simplify ParquetWriter initialization

* Implement Parquet schema context preparation for row-group merging in IcebergRewriteExecutor

* Add minimum average row-group size threshold for Parquet row-group merge

* fixup

* fixup style

Removed unnecessary line breaks in the class documentation.

* fixup style

---------

Co-authored-by: 张文领 <zhangwl9@chinatelecom.cn>

Author: zhangwl9

amoro-format-iceberg/src/main/java/org/apache/amoro/optimizing/AbstractRewriteFilesExecutor.java

@@ -145,7 +145,7 @@ private List<DeleteFile> equalityToPosition() throws Exception {
     return posDeleteWriter.result().deleteFiles();
   }
 
-  private List<DataFile> rewriterDataFiles() throws Exception {
+  protected List<DataFile> rewriterDataFiles() throws Exception {
     List<DataFile> result = Lists.newArrayList();
     TaskWriter<Record> writer = dataWriter();