[AMORO-4163][ams] Fix CommitFailedException when loading legacy mixed-iceberg tables on Iceberg 1.7.2

Iceberg 1.7.2 introduced a breaking change in HadoopTableOperations.commit():
it now uses reference equality (==) to compare the `base` parameter against the
internally cached currentMetadata. If the references differ (e.g. because
versionAndMetadata() refreshes the internal state), a CommitFailedException with
no cause is thrown, which propagates through Thrift and causes table creation to
fail with "update table meta failed".

The commit in newTableOperations() is a best-effort migration step that backfills
REST-based mixed-format properties into legacy table metadata (tables created
before v0.7.0). It is not required for the table to function correctly; a failure
here should not abort table loading. Wrap the call in try-catch and log a warning
so the migration is retried on the next load instead of surfacing as a fatal error.

This fixes the flaky TestInternalMixedCatalogService.CompatibilityCatalogTests
#testNewCatalogLoadHistorical test observed after the Iceberg 1.7.2 upgrade.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: lintingbin

amoro-ams/src/main/java/org/apache/amoro/server/table/internal/InternalMixedIcebergHandler.java

@@ -32,11 +32,14 @@
 import org.apache.hadoop.fs.Path;
 import org.apache.iceberg.TableOperations;
 import org.apache.iceberg.catalog.TableIdentifier;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 import java.util.Map;
 
 /** Table handler for mixed-iceberg format */
 public class InternalMixedIcebergHandler extends InternalIcebergHandler {
+  private static final Logger LOG = LoggerFactory.getLogger(InternalMixedIcebergHandler.class);
   private final boolean changeStore;
   private final CatalogMeta catalogMeta;
 
@@ -75,8 +78,18 @@ private TableOperations newTableOperations(boolean changeStore) {
       }
       org.apache.iceberg.TableMetadata legacyCurrent = legacyTableMetadata(current, changeStore);
       if (!current.equals(legacyCurrent)) {
-        // add rest based mixed-format table properties
-        ops.commit(current, legacyCurrent);
+        // add rest based mixed-format table properties to legacy table metadata
+        try {
+          ops.commit(current, legacyCurrent);
+        } catch (Exception e) {
+          // Commit may fail transiently (e.g. due to Iceberg internal stale-metadata checks).
+          // This is a best-effort upgrade path: the properties will be retried on the next load.
+          LOG.warn(
+              "Failed to update legacy mixed-iceberg table {} with rest-based properties,"
+                  + " will retry on next load",
+              tableLocation,
+              e);
+        }
       }
       return ops;
     }