It depends on how she said it! If she said it kinda of bubbly and smiling really big, it's probably just something she'd say to anyone. BUT if she said it sweetly and softly with a smile on her face, it could mean more. It just depends on how she said it.
i say I love you to my male friend from high school. I'm not going say were "just" friends because our friendship means so much to me. we laugh together, tell each other anything, just hearing from him can make me cry. but we both agree our friendship is uncomplicated. we are truly friends.
Friendship love is trust, respecting each other, and each have each others backs. To me that is a love that comes with a bond in true friendship. I'm talking just friends. I tell my best guy friend I love him all the time. I've also made it very clear we are and always have been platonic friends.
Than again she may honestly be feeling you out for a response. So talk about, I would ask what she means by it. If you believe her than great, if you don't think twice.
If she looked you in the eyes when she said it she has feelings for you. Id never use the word love to describe my affection towards a guy friend unless I meant it OR UNLESS in a joking manner with my head turned away or shaking after they did something stupid and even that's kinda weird. If there's any question of a guy friend being attracted to me and I wasn't attracted to them, I wouldn't want them to get the wrong idea by using such a powerful term. The girl probably really does love you
It means she love you like a friend. If she wanted more than friendship, she'd be more guarded with her emotions. Of course, a little disclaimer, everyone is different. You know her best so...