Something nice that VS Code does when working with Rust code is continuing the current comment when you press Enter while in the comment.

For example, if we had the following code with our cursor at the end of the /// This is a commnent line:

/// This is a comment
fn example() {}

Pressing Enter would result in the comment being extended to the next line:

/// This is a comment
/// 
fn example() {}

From a bit of exploration it seems like we need to do something like this within the extension: https://github.com/rust-lang/rust-analyzer/blob/bc8295255c5bcc293251d47590dcbfd320eaab87/editors/code/src/config.ts#L119-L165