Add delete function to meal claims

[pomkos]

Problem: users keep submitting wrong claims, and asking Pete to manually delete

Solution: allow users to select meal to delete from sqlite db. This involves:

1. streamlit button or checkmark or radio button to indicate item to delete
2. button calls an as of yet unwritten function from db_tool app to remove that specific item from the user's rows

[swindesr]

Make me a contributor to the repo and I will push my PR!

[pomkos]

Merged, but cannot remove because the food items don't show if in the dropdown menu if they were all claimed (by design).

Suggested fix: modify "select an order" dropdown to show only the items that have been claimed when in remove mode.

@swindesr