I was having similar thouhts - multivitamins, fish oil, vitamin D. Don't forget salt and electrolytes. During even a relatively brief disruption the additional physical labor and stress will place a lot of demands on you physically that you don't normally have. Also consider sleep aids and pain relief meds.Keeping track of vitamins and minerals contained in food storage supplies doesn't appear to be a top priority among respondents so far. I think I will stick with supplements to meet any deficiencies in my diet.
The other two benefits of low calorie vegetables (fiber and water) will be provided elsewhere in diet.
Also don't overlook water filtration and purification. Identify at least three places nearby you can get water naturally in the event that city water fails. Keep buckets for drinking water (filtered/treated) and sanitation water (raw) - toilets will continue to work so long as you can keep the tank filled. Also only put filtered/treated water in the "clean" bucket, so you will need two or three. with one reserved for safe water and the other one ot two for water retrieval.
You will die from dehydration much faster than starvation ( three days vs. three weeks).
For food storage in a minimal space go fat heavy. The most stable fats for long term are coconut followed by EVO. Peanut or other nut butters should be high on the list as well. Again, avoif processed fats like "vegetable" oil, canola, corn, anything hydrogenated, mono unsaturated, etc.
The extra activity and stress will mean a need for more than usual calories, especially during cold weather. Canned meats, especially those high in fats are great choices, so Spam, corned beef, and others are good. Canned fish would ideally be packed in oil as opposed to water.