Request backup folder size limit from user and determine backup distribution.

Ask the user if the user wants to set a file limit, and if yes, set a curve that determines what the time interval is to keep backups, (E.g. higher density near near future, than to past.)

The non-linear distribution is because the difference between 5 years ago, and 5 years and 1 day ago is less important than the difference between today and yesterday for (most) humans. So you don't want to keep track of every small change long ago if your backup size is limited.

Hence to apply the distribution over a varying amount of time, delete backups as time goes along (such that you approximate the chosen distribution closer with every distribution).

TODO: Determine whether this distribution pursuit actually approaches the distribution.

No files, tests, or entry points are named. Start by locating the backup handling and user-prompt entry points, then define the file-limit and retention requirements before evaluating whether repeated deletion converges on the proposed distribution. Done means the behavior and convergence criteria are specified and implemented with verification.

Written by the indexing model from the issue text.