The most clear understanding we have from LS is that pali should start the "send" timer before the grpc write, this has the effect of counting network issues against send-to-commit (rather than generate-to-send).

For this reason we should move the markSent() up to where onSent() is called. As a simplification we move the actual onSent calls into their respective providers, which is where the other onGenerate/onCommit/onMaterialized are called from.