I've been messing around a bit with modding this and thought having dates would be neat for some flavor text.
Unfortunately, the ModLoader is kind of whack and pretty limited in what it actually allows. It would be neat for mods to natively allow overriding source classes but that's a lot of work and restructuring for something that likely won't see that much use.
For those curious about code-stuff: I made a mod jar that handles dates and ages but that alone doesn't work with just the mod. Had to build an agent that runs alongside the base game to manipulate the game's bytecode as it loads to overwrite the original classes to inject the modded data. It would be nice to just have one mod file to maintain though.
I'm not talented/experienced enough for this and honestly have no clue what I was doing, but maybe someone who's actually talented in coding (or CSDev but I'd assume you're too busy for that) could look into making a BepInEx/SMAPI-Like Modding-Agent that makes it easier to properly change the game instead of just adding things without having to modify the base game.
EDIT: attached the mod, feel free to mess around. It only adds dates and randomly generated (or set, for custom chosen) birthdays - no extra content. You need java installed because the game is launched via a terminal script (don't launch the game via the .exe, use the .bat-file on windows). BACKUP YOUR SAVES BEFORE YOU USE THIS. The mod actively messes with the game's WorldState. In my limited testing I haven't found the saves breaking when switching on/off the mod, but do be careful.
View attachment CSAgeMod.zip
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