chore: drop the one-release .claude config reads and this repository's old config files #9737

Parent

Refs #5906

Depends on

• refactor(source-control): read the commit and PR convention keys from docs/conventions/source-control.yaml #9725
• refactor(source-control): read the babysit loop keys from docs/conventions/source-control.yaml #9726
• refactor(guardrails): resolve the commit convention from docs/conventions/source-control.yaml #9727
• refactor(ai-slop): move the .claude/ai-slop.json settings to docs/conventions/ai-slop.yaml #9728
• refactor(attribution): move the .claude/attribution.json settings to docs/conventions/attribution.yaml #9729
• refactor(bugs): move the .claude/bugs.md settings to docs/conventions/bugs.yaml #9730
• refactor(docs-naming): move the .claude/docs-naming.json settings to docs/conventions/docs-naming.yaml #9731
• refactor(harness-config): move the .claude/audit-pass.md (its suppressions block) settings to docs/conventions/harness-config.yaml #9732
• refactor(multi-agent): move the multi-agent fenced config block to docs/conventions/multi-agent.yaml #9733
• refactor(review): move the review-digest fenced config block to docs/conventions/review-digest.yaml #9734
• chore(guardrails): reinstall the commit-msg git hooks on operator machines after the convention move #9735

Outcome

No skill reads a team setting from a .claude/<topic>.* file or a fenced config block: the one-release
compatibility reads added by the migration slices are removed, and this repository's old files and blocks are
deleted.

Decisions

• ADR 0064 Decision 1: a plugin's team settings live in one docs/conventions/<concern>.yaml, validated by a
  JSON Schema at plugins/<plugin>/schemas/<concern>.schema.json (Decision 6), checked in CI by
  scripts/check-convention-yaml.sh (Decision 7). Script readers use the shared reader lib/parse-concern-value.sh.
• ADR 0075: layers are plugin default < userConfig < team <home>/<concern>.yaml < personal
  <home>/<concern>.local.<ext>; every resolver reports the layer that supplied each value.
• Migrate per-skill .claude config files to userConfig, one conventions doc, or the cascade (ADR 0018) #5906 (comment 2026-10-04): each reader keeps reading the old file for one release when the new file is
  absent, and this repository keeps its old file until the cleanup slice.

Key interfaces

• Each migrated plugin's config reader; .claude/ and docs/conventions/ in this repository; each plugin's
  retirements.yaml where the plugin records retired surfaces.

Done when

• For each plugin touched, its CHANGELOG shows a released version after the one that added the YAML reader (grep -n on the version heading prints it).
• git ls-tree --name-only HEAD .claude/ lists none of source-control.md, ai-slop.json, attribution.json, bugs.md, docs-naming.json, audit-pass.md.
• git grep -nE "\.claude/(source-control\.md|ai-slop\.json|attribution\.json|bugs\.md|docs-naming\.json|audit-pass\.md)" -- plugins lib scripts prints only CHANGELOG and retirement-record lines.
• git grep -n "yaml config" -- plugins/multi-agent/scripts plugins/review/skills/explain-change/scripts prints nothing.
• Every test file the migration slices named still passes under scripts/run-test-file.sh.
• scripts/check-changelog-fragments.sh --check-required origin/main exits 0.