[kukirin-ui]

Fixes the Console jumping back to the top after a command.

• Each render rebuilt #term with scrollTop 0. Now, after a new block is added or a job finishes, the terminal and the window body scroll to the last line and the > input gets focus (with preventScroll).
• During streaming output the window body also follows the newest line (the terminal already did).
• In-place re-renders keep the user's scroll position if they had scrolled up to read older output; if they were at the bottom, it stays pinned to the bottom.
• No CSS changes, so portrait and landscape layouts are untouched.

Tested in headless Chrome with a mocked Termux bridge (portrait 412x915 and landscape 915x412): after two commands the output is at the last line (exit 0) and the input is focused. On main the same test leaves the view above the end and the input unfocused.