I have been doing some research and I worked out something that can be tasty and healthy too.
Thinking of Parmiggiano cheese which is full of protein
Tuna in bags a brand called johnny west and seafcoal make little bag of 170 gr with simple tuna,tuna with beans or tuna with thai sauce.
Then pita bread or Lebanese bread that can squeeze in quite easy and then brown rise that is fast cooking
a bag of lentils and probably some backcountry food for emergency.
I've gone dairy-free so that's a challenge but found a feta made from coconut oil among other things. Thinking of extending it with hummus and pesto. Bought a salami today. There are yeast-based spreads too that can mimic cheese but I need to avoid soy. Matthew's a vegan so he probably has some good ideas for lunches. I usually have boiled eggs as well and pate though I'm not keen on it and there's not a lot of liver in it. I need to make my own but with working full-time etc. don't want to be spending too much time in the kitchen.