fix(deps): replace step-security/retry and update action pins (#468)

* fix(deps): replace step-security/retry with nick-fields/retry

* chore(deps): update github action sha pins via pinact

* refactor: remove common-retry references from tests and validators

* chore: simplify description fallback and update action count

* docs: remove hardcoded test counts from memory and docs

Replace exact "769 tests" references with qualitative language
so these files don't go stale as test count grows.

.github/workflows/test-actions.yml

@@ -80,7 +80,7 @@ jobs:
           category: github-actions-tests
 
       - name: Upload unit test results
-        uses: actions/upload-artifact@b7c566a772e6b6bfb58ed0dc250532a479d7789f # v6.0.0
+        uses: actions/upload-artifact@bbbca2ddaa5d8feaa63e36b76fdaad77386f024f # v7.0.0
         if: always()
         with:
           name: unit-test-results
@@ -133,7 +133,7 @@ jobs:
           fi
 
       - name: Upload integration test results
-        uses: actions/upload-artifact@b7c566a772e6b6bfb58ed0dc250532a479d7789f # v6.0.0
+        uses: actions/upload-artifact@bbbca2ddaa5d8feaa63e36b76fdaad77386f024f # v7.0.0
         if: always() && steps.check-integration-reports.outputs.reports-found == 'true'
         with:
           name: integration-test-results
@@ -167,7 +167,7 @@ jobs:
         run: make test-coverage
 
       - name: Upload coverage report
-        uses: actions/upload-artifact@b7c566a772e6b6bfb58ed0dc250532a479d7789f # v6.0.0
+        uses: actions/upload-artifact@bbbca2ddaa5d8feaa63e36b76fdaad77386f024f # v7.0.0
         with:
           name: coverage-report
           path: _tests/coverage/
@@ -263,7 +263,7 @@ jobs:
 
     steps:
       - name: Download test results
-        uses: actions/download-artifact@37930b1c2abaa49bbe596cd826c3c89aef350131 # v7.0.0
+        uses: actions/download-artifact@70fc10c6e5e1ce46ad2ea6f2b72d43f7d47b13c3 # v8.0.0
         with:
           pattern: '*-test-results'
           merge-multiple: true