I tend to doubt that such an invocation would be intrroduced officially, simply because it could get very unbalanced as an unlimited-use ability. Basically, given enough time the warlock can completely reshape any dungeon as though moulding clay.
Well, given enough time a cleric could do the same; it's just that the warlock has a much smaller value for enough.
But yeah, Stoneshape does seem rather overpowered as an invocation. Perhaps with some spatial restriction - you can't use the power near where you've already used until X time passes - could restrict it to a sane level.
Yes, it's called Hammer Blast, out of Complete Mage. Lets your eldritch blast do full damage to objects instead of just half. Now you can 'shape' any stone you can hit! (Shaping limited to 'rock with hole in it').