fix(ci): replace fake action SHA pins (niche-actions estate sweep) (#31)

fix(ci): replace fake action SHA pins (estate-wide niche sweep)

Comprehensive sweep across all niche fake SHAs found in the 2026-05-30
estate audit. Substitutions are version-faithful where the intended
version exists; bumped to nearest in-major where the version comment
was also hallucinated (e.g. v3.18.3 of action-slack didn't exist).

All real SHAs verified via gh api repos/<org>/<action>/commits/<sha>.

Provenance: project_estate_fake_action_sha_punch_list_2026_05_30.

Author: hyperpolymath

.github/workflows/quality.yml

@@ -34,7 +34,7 @@ jobs:
           find . -type f -size +1M -not -path "./.git/*" | head -10 || echo "No large files"
 
       - name: EditorConfig check
-        uses: editorconfig-checker/action-editorconfig-checker@8f5440cbefd5428ba6a00b31c5a0b7abcd9a42fd # v2.0.0
+        uses: editorconfig-checker/action-editorconfig-checker@0ab3427a3f09b17c21d489172245be511e0a16ea # v2.0.0
         continue-on-error: true
 
   docs: