Add validated snapshot-only metadata export (D2)

Stream versioned node, namespace and true-session metadata without values or credential-bearing ACL IDs. Validate the selected source, enforce optional output budgets and publish a checksummed manifest atomically last.

Reuse the D1 native snapshot loader and expose iterative preorder traversal without changing the summary CLI. Keep capture and owner uncertainty explicit; do not replay transaction logs or infer recovery completeness.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: arkmish

bin/zkOfflineAudit.cmd

@@ -0,0 +1,23 @@
+@echo off
+REM Licensed to the Apache Software Foundation (ASF) under one or more
+REM contributor license agreements.  See the NOTICE file distributed with
+REM this work for additional information regarding copyright ownership.
+REM The ASF licenses this file to You under the Apache License, Version 2.0
+REM (the "License"); you may not use this file except in compliance with
+REM the License.  You may obtain a copy of the License at
+REM
+REM     http://www.apache.org/licenses/LICENSE-2.0
+REM
+REM Unless required by applicable law or agreed to in writing, software
+REM distributed under the License is distributed on an "AS IS" BASIS,
+REM WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+REM See the License for the specific language governing permissions and
+REM limitations under the License.
+
+setlocal
+call "%~dp0zkEnv.cmd"
+
+set ZOOMAIN=org.apache.zookeeper.server.OfflineAuditExporter
+call %JAVA% -cp "%CLASSPATH%" %JVMFLAGS% %ZOOMAIN% %*
+
+endlocal & exit /b %ERRORLEVEL%

bin/zkOfflineAudit.sh

@@ -0,0 +1,29 @@
+#!/usr/bin/env bash
+
+# Licensed to the Apache Software Foundation (ASF) under one or more
+# contributor license agreements.  See the NOTICE file distributed with
+# this work for additional information regarding copyright ownership.
+# The ASF licenses this file to You under the Apache License, Version 2.0
+# (the "License"); you may not use this file except in compliance with
+# the License.  You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+ZOOBIN="${BASH_SOURCE-$0}"
+ZOOBIN="$(dirname "${ZOOBIN}")"
+ZOOBINDIR="$(cd "${ZOOBIN}"; pwd)"
+
+if [ -e "$ZOOBIN/../libexec/zkEnv.sh" ]; then
+  . "$ZOOBINDIR"/../libexec/zkEnv.sh
+else
+  . "$ZOOBINDIR"/zkEnv.sh
+fi
+
+"$JAVA" -cp "$CLASSPATH" $JVMFLAGS \
+     org.apache.zookeeper.server.OfflineAuditExporter "$@"