UX updates

Author: FumingZhang

src/aks-preview/azext_aks_preview/_help.py

@@ -3868,6 +3868,7 @@
 helps['aks bastion'] = """
     type: command
     short-summary: Connect to a managed Kubernetes cluster using Azure Bastion.
+    long-summary: The command would launch a subshell with the kubeconfig set to connect to the cluster via Bastion. Use exit or Ctrl-D (i.e. EOF) to exit the subshell.
     parameters:
         - name: --bastion
           type: string

src/aks-preview/azext_aks_preview/bastion/bastion.py

@@ -281,6 +281,9 @@ async def _aks_bastion_launch_subshell(kubeconfig_path, port):
             updated_shell_cmd,
             kubeconfig_path,
         )
+        logger.warning(
+            "Use exit or Ctrl-D (i.e. EOF) to exit the subshell."
+        )
         subshell_process = await asyncio.subprocess.create_subprocess_shell(
             cmd=updated_shell_cmd,
             stdin=None,
@@ -327,7 +330,7 @@ async def _aks_bastion_launch_tunnel(bastion_resource, port, mc_id):
             f"{az_cmd_name} network bastion tunnel --resource-group {bastion_resource.resource_group} "
             f"--name {bastion_resource.name} --port {port} --target-resource-id {mc_id} --resource-port 443"
         )
-        logger.debug("Creating bastion tunnel with command: %s", cmd)
+        logger.warning("Creating bastion tunnel with command: '%s'", cmd)
         tunnel_proces = await asyncio.create_subprocess_exec(
             *(cmd.split()),
             stdin=asyncio.subprocess.DEVNULL,