chore: estate-wide chore + stale-path sweep (2026-04-17)

Part of the estate-wide 2026-04-17 cleanup pass. Commits chore-safe
content only: docs, workflow YAML, gitignore, a2ml migration drift,
editorconfig, ncl. Dependency manifests (Cargo.toml/.lock, package.json,
mix.exs, etc.) and source files intentionally held back so no broken
intermediate states where a .rs commit splits from its Cargo.toml.

Also includes stale-path fixes for four ecosystem moves:
  hypatia       -> verification-ecosystem/hypatia
  echidna       -> verification-ecosystem/echidna
  ephapax       -> developer-ecosystem/nextgen-languages/ephapax
  panic-attacker -> games-ecosystem/panic-attacker

Staged files: 12
Held back (source / dep-manifests): 0

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: hyperpolymath

.github/workflows/codeql.yml

@@ -58,7 +58,7 @@ jobs:
         # your codebase is analyzed, see https://docs.github.com/en/code-security/code-scanning/creating-an-advanced-setup-for-code-scanning/codeql-code-scanning-for-compiled-languages
     steps:
     - name: Checkout repository
-      uses: actions/checkout@v4
+      uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
 
     # Add any setup steps before running the `github/codeql-action/init` action.
     # This includes steps like installing compilers or runtimes (`actions/setup-node`

.github/workflows/generator-generic-ossf-slsa3-publish.yml

@@ -24,7 +24,7 @@ jobs:
       digests: ${{ steps.hash.outputs.digests }}
 
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
 
       # ========================================================
       #

.github/workflows/guix-nix-policy.yml

@@ -5,7 +5,7 @@ jobs:
   check:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
       - name: Enforce Guix primary / Nix fallback
         run: |
           # Check for package manager files

.github/workflows/jekyll-gh-pages.yml

@@ -28,7 +28,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout
-        uses: actions/checkout@v4
+        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
       - name: Setup Pages
         uses: actions/configure-pages@v5
       - name: Build with Jekyll

.github/workflows/npm-bun-blocker.yml

@@ -5,7 +5,7 @@ jobs:
   check:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
       - name: Block npm/bun
         run: |
           if [ -f "package-lock.json" ] || [ -f "bun.lockb" ] || [ -f ".npmrc" ]; then

.github/workflows/quality.yml

@@ -6,7 +6,7 @@ jobs:
   lint:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
 
       - name: Check file permissions
         run: |
@@ -36,7 +36,7 @@ jobs:
   docs:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
       - name: Check documentation
         run: |
           MISSING=""

.github/workflows/rescript-deno-ci.yml

@@ -6,7 +6,7 @@ jobs:
   build:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
       - uses: denoland/setup-deno@v1
         with:
           deno-version: v1.x
@@ -33,7 +33,7 @@ jobs:
   security:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
       - uses: denoland/setup-deno@v1
       - name: Check permissions
         run: |

.github/workflows/scorecard.yml

@@ -15,7 +15,7 @@ jobs:
       security-events: write
       id-token: write
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
         with:
           persist-credentials: false
 

.github/workflows/security-policy.yml

@@ -5,7 +5,7 @@ jobs:
   check:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
       - name: Security checks
         run: |
           FAILED=false

.github/workflows/ts-blocker.yml

@@ -5,7 +5,7 @@ jobs:
   check:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
       - name: Block new TypeScript/JavaScript
         run: |
           NEW_TS=$(git diff --name-only --diff-filter=A HEAD~1 2>/dev/null | grep -E '\.(ts|tsx)$' | grep -v '\.gen\.' || true)