Automate forwarding of payments

From: https://habla.news/alby/1690364668026 comment id d4935613aeb825b8a32e20863c926364eff1914aca794505f033683c84f7aa09

Wondering whether it would be interesting to add the ability for the funding to "trickle down". The package developer could add a `recursive` property in the package.json funding area, which would be a decimal between 0 and 1 describing how much of any received funding would be automatically sent further down to other packages devs. It could be achieved even more granularly by combining PkgZap with ZapSlitter.