lint(errcheck): reasons for the nine bare suppressions - #367

…verdicts (#370)

Reviewing cmd/lore and cmd/writ for the issue #365 phase 1b decomposition
surfaced two correctness defects. Both are recorded as their own issues and
plans rather than folded into behavior-preserving refactoring work, where a
semantic change would hide inside an extract-method diff.

Issue #368 — lore deploy silently skips a manifest it cannot load.
parseLoreDeployConfig logs the failure and continues, so the error return is
dead and the //nolint:unparam on it documents a consequence as an intention.
"lore deploy @typo.yaml some-package" deploys some-package and exits 0, having
fulfilled half the request; "lore deploy @typo.yaml" reports "no packages to
deploy", which is the wrong cause. Parsing precedes all deployment, so aborting
costs nothing already done.

Issue #369 — writ segment matching ignores its own suffix grammar. The grammar
is [<project>|common][.<os>][.<distro>][.<arch>][.<custom>...] and segment.go:18
states it, but ParseDirName discards position and Match tests each suffix against
one flat set of every dimension's values. So order is never validated
(common.arm64.Darwin is accepted), position never selects a dimension, and
specificity is a suffix count that cannot rank DISTRO above OS. common.Unix and
common.Darwin both measure 1 on a Mac and tie; the tie is then resolved by
sort.Slice, which is unstable, so the winner is undefined by contract.

The phase 1b verdicts are recorded with measured gocyclo and gocognit for all
nine targets. Ruling 5 is added: treatment is decided per function by whether it
reads as steps. That produced five treatments rather than one — six extract, one
flattens, one keeps an argued suppression, and applyGraphModifications needs no
work at all (gocyclo 7, gocognit 8, under both thresholds; its directive
suppresses nothing).

buildMultiSource is deferred to #369. Its collision predicate at builder.go:280
has zero coverage, confirmed by make cover, and is reachable only through a tie
whose winner is undefined. A behavior-preserving refactor of a predicate with no
defined behavior is not possible.

Phase 1a is marked completed — PR #367, bare nolint directives 18 to 9.

Documentation only; no code changes.
Issues: #365, #368, #369

Co-authored-by: David Noble <[email protected]>