CONTRIBUTING.md asks for one or two sentences over an essay, a pointer
rather than a re-derivation, and module docstrings that orient rather than
document the design. The identity change was written before that guidance
was read, and its comments narrate the reasoning at roughly twice the
length the conclusions need.
Cut to the conclusion and the evidence that makes it credible, keeping
every issue reference: _resolve_identity's docstring 41 lines -> 22 (now
shorter than the two longest already in that file), rekey_entry 23 -> 14,
its module docstring 21 -> 10, resolve_device_key 24 -> 16,
is_usable_device_id 15 -> 8, and the same treatment for the inline blocks
in _resolve_identity, the CONF_DEVICE_KEY note, the redaction rationale,
and the migration suite's module docstring.
Comments only; the suite and the thirteen-mutation sweep are unchanged.
Marc Billow
ccb4a09c65