You're the first person I've heard of who likes ~.
ーI've never heard of anyone who likes ~.
「〜が好きな人はを聞いたことがない」=「初めて聞いた」という言い方です。
I've never heard of anyone who ... で「…な人を初めて聞いた」
ーYou're the first person I've heard of who likes ~.
「〜が好きと言う人はあなたが初めてです」
You're the first person I've heard of who ... で「…という人はあなたが初めてです」
ご参考まで!