fix: Always style primary_title

[Muscraft]

Looking back at my PR switching to secondary_title (#282), I realized that none of the SVGs changed, which seemed odd to me as primary_title should be bolded every time. After looking into it a bit, I realized that annotate-snippets would only use bold text for titles that are in the first group regardless of whether they were primary or secondary. This is a bug as annotate-snippets should respect primary_title and always bold its text, no matter the position of the Group it is in.