[fix](catalog)add custom jar (#23406)

- allow put custom jar in `${DORIS_HOME}/lib/java_extensions/custom_extension` such as `paimon-s3-0.4.0-incubating.jar`
- add some note for paimon and fqdn

bin/start_be.sh

@@ -81,13 +81,14 @@ fi
 preload_jars=("preload-extensions")
 preload_jars+=("java-udf")
 
-for preload_jar in "${preload_jars[@]}"; do
-    f="${DORIS_HOME}/lib/java_extensions/${preload_jar}/${preload_jar}-jar-with-dependencies.jar"
-    if [[ -z "${DORIS_CLASSPATH}" ]]; then
-        export DORIS_CLASSPATH="${f}"
-    else
-        export DORIS_CLASSPATH="${DORIS_CLASSPATH}:${f}"
-    fi
+for preload_jar_dir in "${preload_jars[@]}"; do
+    for f in "${DORIS_HOME}/lib/java_extensions/${preload_jar_dir}"/*.jar; do
+        if [[ -z "${DORIS_CLASSPATH}" ]]; then
+            export DORIS_CLASSPATH="${f}"
+        else
+            export DORIS_CLASSPATH="${DORIS_CLASSPATH}:${f}"
+        fi
+    done
 done
 
 if [[ -d "${DORIS_HOME}/lib/hadoop_hdfs/" ]]; then

docs/en/docs/admin-manual/cluster-management/fqdn.md

@@ -76,13 +76,17 @@ After deploying the cluster according to 'Enable FQDN for new cluster', if you w
 Precondition: The current program supports the syntax 'Alter SYSTEM MODIFY FRONTEND'<fe_ip>:<edit_log_port>'HOSTNAME'<fe_hostname>',
 If not, upgrade to a version that supports the syntax
 
+>Note that.
+>
+> At least three followers are required to perform the following operations, otherwise the cluster may not start properly
+
 Next, follow the steps below:
 
 1. Perform the following operations on the Follower and Observer nodes one by one (and finally on the Master node):
 
    1. Stop the node.
    2. Check if the node has stopped. Execute 'show frontends' through the MySQL client to view the Alive status of the FE node until it becomes false
-   3. set FQDN for node: `ALTER SYSTEM MODIFY FRONTEND "<fe_ip>:<edit_log_port>" HOSTNAME "<fe_hostname>"`
+   3. set FQDN for node: `ALTER SYSTEM MODIFY FRONTEND "<fe_ip>:<edit_log_port>" HOSTNAME "<fe_hostname>"`(After stopping the master, a new master node will be selected and used to execute SQL statements)
    4. Modify node configuration. Modify the 'conf/fe. conf' file in the FE root directory and add the configuration: `enable_fqdn_mode = true`
    5. Start the node.
 

docs/en/docs/lakehouse/multi-catalog/paimon.md

@@ -60,6 +60,11 @@ CREATE CATALOG `paimon_hdfs` PROPERTIES (
 
 #### S3
 
+>Note that.
+>
+> user need download [paimon-s3-0.4.0-incubating.jar](https://repo.maven.apache.org/maven2/org/apache/paimon/paimon-s3/0.4.0-incubating/paimon-s3-0.4.0-incubating.jar)
+> Place it in directory ${DORIS_HOME}/be/lib/java_extensions/preload-extensions and restart be
+
 ```sql
 CREATE CATALOG `paimon_s3` PROPERTIES (
     "type" = "paimon",
@@ -73,6 +78,12 @@ CREATE CATALOG `paimon_s3` PROPERTIES (
 
 #### OSS
 
+>Note that.
+>
+> user need download [paimon-oss-0.4.0-incubating.jar](https://repo.maven.apache.org/maven2/org/apache/paimon/paimon-oss/0.4.0-incubating/paimon-oss-0.4.0-incubating.jar)
+> Place it in directory ${DORIS_HOME}/be/lib/java_extensions/preload-extensions and restart be
+
+
 ```sql
 CREATE CATALOG `paimon_oss` PROPERTIES (
     "type" = "paimon",

docs/zh-CN/docs/admin-manual/cluster-management/fqdn.md

@@ -76,13 +76,17 @@ K8s 部署 Doris 的方法请参考[K8s 部署doris](../../install/k8s-deploy.md
 前提条件：当前程序支持`ALTER SYSTEM MODIFY FRONTEND "<fe_ip>:<edit_log_port>" HOSTNAME "<fe_hostname>"`语法，
 如果不支持，需要升级到支持该语法的版本
 
+>注意：
+>
+> 至少有三台follower才能进行如下操作，否则会造成集群无法正常启动
+
 接下来按照如下步骤操作：
 
 1. 逐一对 Follower、Observer 节点进行以下操作(最后操作 Master 节点)：
 
     1. 停止节点。
     2. 检查节点是否停止。通过 MySQL 客户端执行`show frontends`，查看该 FE 节点的 Alive 状态直至变为 false
-    3. 为节点设置 FQDN: `ALTER SYSTEM MODIFY FRONTEND "<fe_ip>:<edit_log_port>" HOSTNAME "<fe_hostname>"`
+    3. 为节点设置 FQDN: `ALTER SYSTEM MODIFY FRONTEND "<fe_ip>:<edit_log_port>" HOSTNAME "<fe_hostname>"`（停掉master后，会选举出新的master节点，用新的master节点来执行sql语句）
     4. 修改节点配置。修改 FE 根目录中的`conf/fe.conf`文件，添加配置：`enable_fqdn_mode = true`
     5. 启动节点。
     

docs/zh-CN/docs/lakehouse/multi-catalog/paimon.md

@@ -60,6 +60,11 @@ CREATE CATALOG `paimon_hdfs` PROPERTIES (
 
 #### S3
 
+>注意：
+>
+> 用户需要手动下载[paimon-s3-0.4.0-incubating.jar](https://repo.maven.apache.org/maven2/org/apache/paimon/paimon-s3/0.4.0-incubating/paimon-s3-0.4.0-incubating.jar)
+> 放在${DORIS_HOME}/be/lib/java_extensions/preload-extensions目录下并重启be
+
 ```sql
 CREATE CATALOG `paimon_s3` PROPERTIES (
     "type" = "paimon",
@@ -73,6 +78,11 @@ CREATE CATALOG `paimon_s3` PROPERTIES (
 
 #### OSS
 
+>注意：
+>
+> 用户需要手动下载[paimon-oss-0.4.0-incubating.jar](https://repo.maven.apache.org/maven2/org/apache/paimon/paimon-oss/0.4.0-incubating/paimon-oss-0.4.0-incubating.jar)
+> 放在${DORIS_HOME}/be/lib/java_extensions/preload-extensions目录下并重启be
+
 ```sql
 CREATE CATALOG `paimon_oss` PROPERTIES (
     "type" = "paimon",