Core engine: git io, diff parsing, byte-exact apply, shape classes, invariants, and plan-document assembly.
The canonical enumeration (git diff -U0 --no-renames) processes every file
with no exclusions (ADR 0005); the rename-detected view (-M) only annotates
it (ADR 0003). Repo config tunes classification hints and can never remove
anything from enumeration (ADR 0012).