ChartRead: registration and results hashes (post hoc deposit)

Deposited after every model run and every rating sheet of the study. It proves only that these files have not changed since the deposit date; it does not establish that any registration preceded its data. The registrations' own hashes were recorded earlier in the authors' local issue tracker (bd), and the repository's first commits of them postdate their data (deviation 26 of docs/reference/chartread-deviations.md, released at https://github.com/OJamals/chartread). manifest.json lists the SHA-256 of the eight ChartRead registration documents and of every frozen item set, key file, manifest and model response file; it holds file names and hashes only, no item text, response text or rater data.