fix: Co-authored-by and Signed-off-by auto-wrapping

[sogladev]

PR Description

In addition to ignoring footnote, also ignore Co-authored-by and Signed-off-by

This no-wrap detection only needs to check for leading ASCII, so we can use a fixed bytebuffer. This avoids repeated heap allocs when building strings

• Closes Auto-wrap breaks long co author string #5216

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