anomalyco
feat: add messages_last_user command to scroll TUI to last user message (implements #4847)
Resolves #4847.
This PR adds a new messages_user_last command that scrolls/jumps the TUI viewport to the last message sent by the user.
This improves ergonomics and UX by providing the user with a way to easily jump back to the last message, which is helpful when the model has generated several screens full of output and they'd like to review it, which can occur frequently when the user is paying attention to another window or steps AFK while the model works. Having a dedicated command for this purpose that can be invoked with a single keystroke is more ergonomic than using the session timeline, which can accomplish the same goal but requires more keystrokes to do so.
The command is not currently bound to any key by default, leaving it up to the user to bind it to their preferred key in their opencode.jsonc, but I'm open to adding some default keybinding if a maintainer has a suggestion as to what key they think is appropriate.
