As the title suggests, how do I use the feature pinned code blocks? During the chat process, when I click the button pinned code blocks, I can pin a certain code block to the top of the chat, but this pinning seems to only be for pinning, with no other function? So is the purpose of this button to facilitate viewing code blocks? If I want to pin multiple code blocks to the top and share the corresponding code blocks across multiple chats, is that possible?