Describe the solution you'd like
store levels separately from XP and only store the XP progress to the next level

Why is this feature needed
The current limit of levels is based on the max xp stored, which is a long max_value. By splitting them, the progress xp to next level can be as large as the long max each level while the max levels can also be the max long, thus squaring the total possible XP values.

Describe alternatives you've considered
leaving XP as is.

Additional context
A migration from old storage to new will be necessary.