Trashcan max size option

Feature description

Thank you for making Syncthing.
I love it. It is the only free tool that lets me sync folders from android to PC/server.
I am using it to move my Signal backups to my server, they are generated each night as new file and newest two files are kept.
I need some form of file versioning but none fits my needs.
Easiest change would be a setting for the Trash Can File Versioning to delete oldest files if a set size limit is reached.

Problem or use case

Currently I am only able to set number of days old versions are kept. With daily backups this is a huge size quickly. But when my phone stops pushing backups I don't want Syncthing to delete old versions.

Alternatives or workarounds

idk

also it would be great to have a file size info in the File Versioning tile of each folder

Start by tracing the Trash Can File Versioning setting and its current age-based retention behavior. Determine where a maximum-size limit would fit, how oldest files should be removed without deleting versions during backup inactivity, and how the File Versioning tile could expose size information; done means the requested retention behavior and size display are specified and tested.