The answer from user rumtscho ♦ put me on the right track so, as now I had a way to contact the producer company, I wrote them an email asking the same question I posted here: what's the idea behind it, and how should it be eaten?
They replied me back (quite quickly, too), and this is their answer:
The kind of cheese that you bought is called Shelal -it is Arabic
cheese and it is very specific.
It is hard at the beginning and salty -the saltiness will decrease if
you separate it into strings and soak it in water. This way it gets
softer. When softer it starts dividing into strings more easily.
Then you may season it with olive oil and some dry spices. You may
also put it inside Arabic bread or two slices of bread with some olive
oil and toast it. Enjoy!
Needless to say it went straight from its bag into a bowl full of water after, like, 30 seconds :-D
It has now soaked for nearly 24 hours and yes, it has changed quite a bit. There are parts of it which are still hard, but the saltiness is balancing well and it is becoming way softer. Note that I prefer to err on the side of safety, so I'm soaking it into the fridge; maybe outside of the fridge it would soften faster, dunno.
As of now, it is already quite good. It's like...it has the consistence of a braided mozzarella but tastes like a yellow cheese, quite interesting.
But...I'm not sure if it's worth the hassle. Ok, as I said it's interesting and good, so from that point of view it's worth it. But on the other hand after having put it into the water I automatically renamed it "Ikea cheese", as you buy it disassembled and you have to reassemble it back yourself :-D
It could make a lot of sense, actually, the fact that it can be bought in jars (or maybe it must be bought in jars, and I've been able instead to buy only a couple of pieces thanks to my mastering of Bulgarian language; that is, I know nothing of it so shop owners usually sell me whatever I ask :-D)
Once bought the entire jar, it will always be at hand reach; moreover it should be easy to transport, restoring it requires just a bowl and some water, so I can see it a perfect fit for people traveling with a motorhome.
Finally -and I'll update the post as soon as I try to do it- being mostly dry it should be perfect for topping home made pizza, as it will not soak the dough.