Looking good!

Well I generally try to don't snack and have just two good meals per day. But If I have to, apart from meat of all sorts for big meal of the day, I personally use:

Eggs (whatever form, hard boiled for traveling etc);

Sausages, salami etc (but one have to be careful to look for ingredients);

Salmon can be easily eaten even raw sushi style, smoked salmon on the other hand can be stored for some time;

Hard cheeses survive for very long time, they are useful as a snack;

Nuts;

Tartare steak - just a little bite with spoon directly from the fridge 😅

All sorts of fish (fillets) can be prepared like in a minute on a pan, same with a bunch other sea creatures;

China style chicken pieces with nuts, eggs, just quickly prepared on a pan.