refactor: move errors/redaction/device into src/kernel — Phase 5 slice 3

[thymikee]

What

Relocates the foundational primitive trio — errors.ts, redaction.ts, device.ts — from src/utils/ into the kernel/ layer (joining snapshot.ts from slice 2 / #932), per the target folder DAG in plans/perfect-shape.md §5.5.

A pure path codemod, no behavior change.

Why these three, atomically

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 (321 importers); device.ts is the §5.5-named headliner (144). Moving all three in one atomic move avoids a half-state where one would import another across the utils/↔kernel/ boundary.

How

Imports were rewritten by a resolve-based codemod: it compares each specifier's resolved absolute path to the moved files before rewriting, so unrelated same-named files (commands/management/device.ts, etc.) are left untouched. 481 import sites across 400 files. Intra-cluster imports (device → ./errors, errors → ./redaction) need no change — the three stay co-located in kernel/.

Also updated: two platform-descriptor doc comments, the fallow health-baseline key for device.ts, and the contracts-schema-public guard (asserting the error helpers pull no diagnostics/node: deps) now reads kernel/errors.ts.

Verification

• tsc --noEmit exit 0; kernel/ files import only within kernel (no upward deps)
• oxfmt + oxlint src --deny-warnings clean (no unrelated drift — every changed file's diff is an import rewrite)
• rslib build exit 0
• full vitest run → 2870 pass. The only failures were the known-flaky android-fill timing tests under full-suite CPU load (5s timeouts); they pass 92/92 in isolation, and a pure import-path move cannot affect fill logic.
• fallow audit --base origin/main → ✓ no issues in 406 changed files
• Layering Guard grep empty; no stale utils/{errors,redaction,device}.ts references anywhere (src, test, configs, baselines)

Note

Large but mechanical (the inherent cost of relocating the most-imported foundational modules) — best merged promptly to avoid import-drift conflicts. kernel/ now holds snapshot · errors · redaction · device; remaining kernel members (contracts.ts, and command-result/capabilities once their core/-descriptor coupling is broken) follow in later slices.

[github-actions]

Size Report

Metric	Base	Current	Diff
JS raw	1.4 MB	1.4 MB	0 B
JS gzip	453.3 kB	453.3 kB	-14 B
npm tarball	558.5 kB	558.6 kB	+21 B
npm unpacked	2.0 MB	2.0 MB	0 B

Startup median (7 runs, lower is better):

Scenario	Base	Current	Diff
CLI --version	27.4 ms	27.5 ms	+0.1 ms
CLI --help	48.2 ms	48.1 ms	-0.2 ms

Top changed chunks:

Chunk	Raw diff	Gzip diff
dist/src/9722.js	0 B	+3 B
dist/src/2577.js	0 B	-2 B
dist/src/cli.js	0 B	+2 B
dist/src/9919.js	0 B	-2 B
dist/src/apps.js	0 B	-2 B

[thymikee]

I checked the path-move surface and the source imports look mechanically clean: the three files are 100% renames into src/kernel/, git diff --check is clean, there are no remaining source/test imports of src/utils/{device,errors,redaction}.ts, and src/kernel does not import upward.

One cleanup before merge: there are still current repo guidance/doc references to the old paths:

• AGENTS.md still names src/utils/device.ts in the Apple-family sync rule and src/utils/errors.ts for normalizeError.
• docs/adr/0009-apple-platform-consolidation.md still points resolveApplePlatformName at src/utils/device.ts.
• plans/apple-platform-consolidation.md still labels DeviceInfo as src/utils/device.ts.

plans/perfect-shape.md also still has a historical utils/device.ts mention; that one may be intentionally describing the pre-move diagnosis, but the current guidance files above should move to src/kernel/device.ts / src/kernel/errors.ts so future agents do not follow stale paths.

[thymikee]

Done — pushed c2c7d56. Updated the three current guidance files to point at the new src/kernel/ paths:

• AGENTS.md: Apple-family sync rule → src/kernel/device.ts; normalizeError → src/kernel/errors.ts
• docs/adr/0009-apple-platform-consolidation.md: resolveApplePlatformName → src/kernel/device.ts
• plans/apple-platform-consolidation.md: DeviceInfo → src/kernel/device.ts

Left plans/perfect-shape.md's utils/device.ts mention as-is per your note — it's in the §3 diagnosis describing the pre-move state (the §5.5 DAG already documents the kernel destination). Happy to update that too if you'd prefer it reflect the post-move reality.

[thymikee]

Thanks, the stale-path cleanup from the prior review is addressed in c2c7d56. One remaining sequencing blocker: GitHub now reports this branch as DIRTY against current main, so it needs a rebase/conflict cleanup before it can be considered ready-for-human. I am leaving the ready label off until the branch is clean again.

[thymikee]

Re-checked current clean head e196be5 after the rebase. The prior stale-path cleanup is present, the PR is now CLEAN, all 21 checks are green, git diff --check is clean, and the current merge diff remains the intended mechanical utils/{device,errors,redaction} → kernel/ move plus import rewrites/doc path updates. I do not see remaining actionable blockers, so I am marking this ready-for-human.

[thymikee]

Rebased onto current main and force-pushed (e196be5). Because main had advanced (#933 + #936 added new files importing the old utils/{errors,device} paths), I redid the move fresh on the new base so the resolve-based codemod picked up the new importers — 483 sites across 402 files. The branch is now MERGEABLE (no longer DIRTY). Re-verified on the new base: tsc 0, oxfmt+oxlint clean, rslib build 0, full vitest 2877 pass, fallow ✓ no issues in 411 changed files, Layering Guard empty, no stale utils/{device,errors,redaction} references (except the intentional perfect-shape.md diagnosis mention).