Tabs are so narrow I keep closing them by accident: make them wider with consistent width

[wrymn]

I really want to like T3, and I use it day to day on a big Unity repo, but a few UI basics make it frustrating. This is one of them (see also #24017, where the Files panel cuts off every file name).

The × covers a big chunk of the tab, so when I click to switch tabs I often close one instead.

Suggestion: wider tabs with the same width for every tab and a separate close button, the way browsers, Codex and Claude Code do it.

Related but different: #17986 moves the close button to the right. This is about tab width: wider tabs that all have the same width, so the label is a big, predictable click target.