I think I have worked out most of the issues I ran into while designing, building and testing this food-for-litter birdfeeder. I'm ready to stop tweaking and finalize the electronics and dispense mechanism. There is still tons of room for improvement and optimization, but what I have so far is simple and works reliably so it's time to make some PCBs. Excluding the PCBs, the electronic components cost 10-15 EUR. If you've been building electronics for a bit, you probably already have everything you need.

I'm hesitant to "finalize" the enclosure or deposit/dispense assembly - it is also simple and functional but once you have the electronics and dispense mechanism almost any enclosure will work provided it is light-tight-ish and the dispense and deposit pathways have bends to block reflections from outside. I don't know how commonly accessible wine gift boxes are and there are so many possibilities that may suit your needs or material availability better. I'll provide more details about the current enclosure as a reference design.