Bug in Table.to html() method causing incorrect HTML output

Bug in Table.to html() method causing incorrect HTML output: a task in harbor-swesmith-rl-artifacts: Harbor SWE-Smith 强化学习数据产物 (Harbor dataset). After recent changes, the to html() method in the Table class is generating incorrect HTML output. The issue appears to be related to the header padding…

The task

After recent changes, the `to_html()` method in the `Table` class is generating incorrect HTML output. The issue appears to be related to the header padding logic and string formatting.

Part of keryszhan/harbor-swesmith-rl-artifacts.