I think I have to agree with Xcodes mostly, mind blank and foresight don't interact.
-Mindblank prevents certain (defined) divinations from affecting you, period.
-Foresight doesn't give you any information on you at all, nor does it target any creatures around you, it gives you information on events happening around you.
-Foresight doesn't suck. I'm not sure shapechange is viable to use all the time like you want it, so foresight is your other option(there are just some times that you can't be a giant turtle... at the kings ball or some such).
-With persisting abilities, their differences don't really matter, just persist both of them, who cares.
Where I disagree is that a properly built AMF rogue assassin could take out a caster... a caster isn't usually prepared ALL the time.
I have to concede the point that many have made though about divinations, they really mess up a rogue. Unless he figures out a way to get immune to divinations, your right he's in trouble.
The argument that a cleric is the best option seems flawed from the get go. Sure a cleric could take out a caster, but its a top tier class for a reason. Since it can pretty much do anything, you'd be hard pressed to find a build that has the slightest problem with any melee class.
I think the most likely thing that could satisfy the OP is a sorcerer focused only on dispel/spell battling
a Sorcerer build for ~ 10 levels + initiate of the seven fold veil 7, + at least one lvl archmage with (mastery of counterspelling)
assuming the sorcerer's spell selection is ONLY meant to take out casters then the melee should make short work of them. they would only have divinations/dispels/fort or reflex targeting save or dies etc. melees should laugh at the save or dies, and the sorcerer wouldn't have the right spells to deal with melee.
3 things though:
#1 vs such a build the melee may have trouble with the IOTSV part. but even the veils aren't insurmountable, there are items that will get them past... and so would AMF.
#2 the sorcerer would have to have teleport, its got to, to deal with a high level caster. the melee has to shut that down if it wants any chance.
#3 the sorcerer will have dispel, and chain dispel, which could shut off melee's items. they'd need to be prepared to counter that with a ring of counterspells or such.