* refactor: move errors/redaction/device into src/kernel — Phase 5 slice 3
Relocates the foundational primitive trio from src/utils/ into the kernel/ layer
(joining snapshot.ts from slice 2), per the target folder DAG in
plans/perfect-shape.md §5.5. A pure path codemod, no behavior change.
They form a closed cluster — device -> errors -> redaction, with redaction a
leaf — so kernel/ takes no upward dependency, and every importer becomes a clean
downward import toward kernel. errors.ts is the most-imported module in the
tree; device.ts the §5.5-named headliner. Moving all three atomically avoids a
half-state where one would import another across the utils/kernel boundary.
Imports rewritten by a resolve-based codemod (compares each specifier's resolved
path to the moved files, so the unrelated commands/management/device.ts and
other same-named files are untouched): 483 sites across 402 files. The two
platform-descriptor doc comments and the fallow health baseline key for
device.ts are updated to the new path; the contracts-schema-public guard that
asserts the error helpers pull no diagnostics/node: deps now reads kernel/.
Verified: tsc --noEmit, oxfmt + oxlint --deny-warnings, rslib build, full vitest
suite (2877 pass), fallow audit clean (411 changed files), Layering Guard empty;
kernel/ files import only within kernel.
* docs: update guidance references to kernel/{device,errors} after the move
AGENTS.md (Apple-family sync rule + normalizeError), ADR-0009, and
plans/apple-platform-consolidation.md still named the old src/utils/ paths.
Point them at src/kernel/. plans/perfect-shape.md's utils/device.ts mention is
left as-is — it describes the pre-move diagnosis.
Michał Pierzchała