Design fixes + hide email tab if not a company or a person (#3720)

Design fixes + hide email tab

Co-authored-by: Thomas Trompette <thomast@twenty.com>
Co-authored-by: Lucas Bordeau <bordeau.lucas@gmail.com>

packages/twenty-front/src/modules/activities/emails/components/EmailThreadMessageSender.tsx

@@ -23,6 +23,7 @@ const StyledAvatar = styled(Avatar)`
 `;
 
 const StyledSenderName = styled.span`
+  color: ${({ theme }) => theme.font.color.primary};
   font-size: ${({ theme }) => theme.font.size.sm};
   font-weight: ${({ theme }) => theme.font.weight.medium};
   overflow: hidden;