Resume picker shows raw XML tags for slash commands like /clear

Description

The /resume conversation picker displays raw internal XML markup instead of clean preview text for conversations where slash commands (like /clear) were the last action.

Expected behavior

The resume picker should render a clean preview, e.g. showing /clear or a summary of the conversation.

Actual behavior

The resume picker shows raw internal markup like:

<command-name>/clear</command-name> <command-message>clear</command-message> <command-args></comman…

Steps to reproduce

1. Start a Claude Code session
2. Run /clear
3. Exit the session
4. Run claude /resume
5. Observe the conversation list - the preview text for that session shows raw XML tags

Additional context

This affects any conversation where the last visible "message" was a slash command. Since /clear is commonly used, many conversations end up with this garbled preview text.