So if this is not something player called for but simply your calling for a check because you know the Wizard has high intelligence and proficiency with history it might be that while the player doesn't think to actively consider a painting you recognize that perhaps the character might know something interesting or useful so you as GM call for the roll without them asking. Since it might not be anything more than a glance or at a painting at a wall, there is no reason for the cleric to assume the Wizard needs guidance on this check.
Sure, I would totally see that. The wizard had forsight (rule #1) and asked for it so the Cleric inherits that. If however rule #2, I would ask what other players are doing in the mean time, are they just sleeping in the library board out of their minds while the wizard studies? If a second character wanted to find a shop at the same time, since the spell only lasts for 10 mins and its concentration other characters would not benefit from it in an investigation check to find a shop they don't know of (AKA hidden from view, so investigation). Also, the Cleric is bound to the Library and Wizard as well since the 10 mins will not carry through the hole task. So negotiations with salesmen or watching the door for someone who might catch them in the forbidden section of the library will not get guidance at the same time.
If a players decides their PC does something they call for the check. Example: Player, "I would like to investigate the room"
If events or things unseen to your players controlled by the GM could effect them, the GM calls for a check even if not asked because players couldn't possibly know to call for the check.
Example: The players are walking through the mansion, one painting in GM notes has special meaning to one player. If that player walks by it, the GM might call for a perception check to be aware of the painting. The player wouldn't know of the painting on a fail nor the Cleric to grant them guidance, but on a success something might trigger base on skills they are proficient with or there back story. As a GM you feel the world to players with respect to characters. So unless you want to teach your players to investigate every ... single .... room... sometimes you let them walk and give them a roll for unexpected information.
Look at it this way, If you don't let players call for rolls your stealing player free agency but if you don't give rolls to players who didn't call for them when their character in game would based on its abilities is also stealing free agency through omission since your denying the characters abilities and therefore the players character choices and roles. If a players says, "I scout ahead"... that player is the scout, that player did not call for a perception check but is constantly searching perhaps for hours, and as a GM when that player could perceive something, I as GM, will give them a role. They will not get guidance however, because the Cleric would have to cast guidance on that scout every ten minutes all day until they found something. Their is no acceptable forsight for the cleric to do that, but their is a expectation of the player running the "scout" to keep watch for surprises for the duration. Also, if I were to have the scout player call perception checks for being the scout, they would need to roll every few feet in every dungeon or forest at all times... which would be EXTREMELY painful for everyone. The non-scout players still have passive perception if the scout misses something but they will never get higher than that and "eyes of the eagle" for example would apply to the scouts GM called perception roll, so I am not ignoring their items, character choices, or party roles they have picked but instead respecting them by call the role for them when it is relevant and they would not know to do so since the world only exists in my head as GM and creator of the world they are in.
