With an ice pack, I would trust any of the followung:

Tofu or tempeh
Seaweed snacks
Carrots or bell peppers with guacamole pack
Hummus or baba gnoiush with green beans, cucumber, grape tomatoes, etc....
Pumpkin seeds, sunflower seeds, nuts.....
Celery with almond butter
Olives
Avocado with salt and a spoon!
Edamame or dry roasted edamame
Miso soup packet of your office has a hot water thing for tea
Very dark chocolate
A thermos or coconut milk- you could add.protein powder or something like stevia and raspberry extract
Berries
Dried coconut flakes
Flaxmeal to make a hot cereal with water and toppings like berries or nuts
Granola made from nuts, seeds and coconut
Almond or coconut yogurt (kite hill makes a great unsweetened one)
Shiratki with sesame peanut sauce and carrots/ cucumber
Leftover roasted veggies like balsamic brussels, peppers, etc....
Spaghetti squash with vegan pesto and nutritional yeast
Broccoli with sesame peanut dip