Move flask/tanning hide iuse function to iuse_actor

Fixes #10372

Moves the iuse functions for yeast flask and tanning hide/fur into an `iuse_actor`, loaded from json.
The kiln now uses the same function, working like the tanning hide outside of the reality bubble.
Because the new actor uses the items age (based on the birthday) and the transformation loaded kiln to lit kiln does not update the birthday, it would use the wrong birthday (the one from the loaded kiln, when it had been crafted, not when it had been lit). Therefor the intermediate step of loaded kiln has been removed. Crafting automatically creates a loaded and lit kiln.

This also adds text to the items description saying how long it will take until the item is ready.