Do you fold or blend the olives in a fougasse?
Fougasse is a French bread, akin to Italian foccacia.  It is most frequently &quot;filled&quot; with herbs, but there are versions with olive and shallot or onion.  I am sure you can add other items as well.  It is frequently cut and/or slit into a leaf shape just before baking.  The processes of both are similar.  Make the dough, proof, punch down, rest, shape (perhaps another rise), and bake.
In terms of your mix-ins, I would knead them in after the first proof and punch down.  Then, rest before shaping. You might also add another rise at this stage.  The mix-in step might be messy at first, especially if using oily ingredients.  Keep at it, the dough will eventually smooth out.  Remember, each time you manipulate the dough you are impacting the gluten network.  It will tighten up and become difficult to shape.  So the resting step is important for final shaping.