Hi there,
Congrats on the new job! And good luck tomorrow! I'm so excited for you.
Like Legs Akimbo, I mostly pack leftover dinner as lunch the next day. But for some healthy lunch ideas, I usually make whole grain salads with ingredients like chickpea, quinoa, brown rice pasta, spelt pasta, etc and toss them with sautéed vegetables and a bit of cheese for added flavor/texture. For extra protein, add some chicken, fish, egg, or tofu. Think deli display cases at Whole Foods. Unless you use mayo or dairy-based dressings, these kinds of salads keep pretty well at room temperature too.