How can something forbidden by the Messenger of Allah, peace and blessings be upon him, be merely disliked (makruh) and not prohibited (haram), considering the hadith "When I forbid you from something, then avoid it," which indicates that prohibition implies حرمة (tahreem - unlawfulness/prohibition)?

The fundamental principle is that a command (الأمر) signifies obligation (وجوب) according to the majority of scholars, and a prohibition (النهي) signifies حرمة (prohibition/unlawfulness). The majority supports this, citing the Almighty's saying: "And whatever the Messenger gives you, take it; and whatever he forbids you from, abstain." (Quran 59:7). However, a prohibition may signify karahah (dislike/disapproval) rather than tahrim (prohibition/unlawfulness) if there is an indicator (qarinah). For example, Umm Atiyyah said: "We were forbidden from following funerals, but it was not made binding upon us." This means it was a karahah tanzeeh (dislike of avoidance) not a tahrim. Another example is: "Do not ask about things which, if made plain to you, would trouble you." (Quran 5:101). Here, the prohibition signifies karahah and not tahrim, due to the presence of an indicator that shifted the word from its apparent meaning.