HBASE-30288 Fix WALPlayer bulk output table mappings

[Sigma-Ma]

JIRA: https://issues.apache.org/jira/browse/HBASE-30288

What changes were proposed in this pull request?

This PR makes WALPlayer honor source-to-target table mappings when generating bulk-output HFiles.

The bulk mapper now builds the mapping from TABLES_KEY and TABLE_MAP_KEY, keeps source table names for WAL filtering, and emits mapped target table names in multi-table composite keys. The bulk job is also configured with target table descriptors and region locators.

The existing bulk-load test now uses distinct source and target tables, with the target table pre-split using a different region layout, and verifies that the generated HFiles can be loaded into the mapped target table.

Why are the changes needed?

Before this change, the bulk-output path ignored the target table mappings. WALKeyValueMapper emitted source table names, and createSubmittableJob configured HFileOutputFormat with source table metadata.

As a result, HFiles could be generated under the wrong table path and with region boundaries or table descriptors belonging to the source table, preventing them from being correctly bulk-loaded into the intended target table.

How was this patch tested?

mvn -pl hbase-mapreduce -am \
  '-Dtest=TestWALPlayer#testWALPlayerBulkLoadWithTableMappingAndOverriddenTimestamps' \
  -Dsurefire.failIfNoSpecifiedTests=false \
  test

mvn -pl hbase-mapreduce -am -Dtest=TestWALPlayer -Dsurefire.failIfNoSpecifiedTests=false test