NNS sync status

The authoritative machine-readable file is:

sync/nns_source.json

Layer	Repository	Commit	Role
R source	OVVO-Financial/NNS	See manifest	Statistical and R API source of truth
C++ core	OVVO-Financial/NNS-core	See manifest	Accepted portable native core
Python	OVVO-Financial/NNS-python	Current repo	Python API, parity, packaging, examples

Native code enters Python only through the accepted public NNS-core snapshot vendored under:

extern/NNS-core

R behavior is checked directly against live R NNS when required, and against the committed parity cache in ordinary CI.

Notes on manifest fields

r_src_tree_hash records the git tree object hash of the vendored R src/** tree (tools/NNS/src). The r_commit and core_commit fields are populated by the sync automation when an upstream NNS or NNS-core event fires; until a sync event records them they may read unknown. The r_version is taken from the vendored R DESCRIPTION (13.0).