Lack of Style Options for Spaces in Full Help View Columns

[rrrodzilla]

https://github.com/charmbracelet/bubbles/blob/a9344b59531d1b947978485dea07c5597299889a/help/help.go#L197-L201

In the FullHelpView function, the spaces within the columns created by lipgloss.JoinHorizontal do not have dedicated style options. This results in inconsistent styling, especially when a background color is applied to the terminal. As shown in the attached screenshot, the spaces remain unstyled with no ability to apply custom styles, leading to visual discrepancies.

This issue is similar to the one described in issue #571, where the ShortHelpView function lacks style options for spaces between the key and description.

Screenshot:

To resolve this issue, I suggest wrapping the JoinHorizontal call in a Render call of the FullSeparator style. This would allow the other styles to override anything not set by the FullSeparator style, effectively styling the whitespace.

If you settle on an approach, I'm happy to implement it and provide a PR. Thanks again!