gate guard, runtime spec, Node 24 actions

.github/workflows/ci.yml

@@ -14,6 +14,11 @@
 
 name: CI
 
+# Action versions are the Node 24 native releases (checkout@v5, setup-node@v5,
+# setup-python@v6). The v4/v5 generation targets Node 20, which the runners now
+# force onto Node 24 with a deprecation warning on every job - working today,
+# a hard failure whenever GitHub drops the shim.
+#
 # Jobs run on the org's self-hosted "arc-runner-set" (enterprise
 # ge-aerospace-runner-group, Linux). GitHub-hosted runners are blocked by the
 # org IP allow list (hosted Azure runner IPs are not allow-listed -> checkout
@@ -34,8 +39,8 @@ jobs:
   backend:
     runs-on: arc-runner-set
     steps:
-      - uses: actions/checkout@v4
-      - uses: actions/setup-python@v5
+      - uses: actions/checkout@v5
+      - uses: actions/setup-python@v6
         with:
           python-version: '3.14'
           cache: pip
@@ -45,7 +50,7 @@ jobs:
   naming:
     runs-on: arc-runner-set
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v5
       - run: bash scripts/check-naming-and-style.sh
 
   gates:
@@ -58,8 +63,8 @@ jobs:
     # it again.
     runs-on: arc-runner-set
     steps:
-      - uses: actions/checkout@v4
-      - uses: actions/setup-python@v5
+      - uses: actions/checkout@v5
+      - uses: actions/setup-python@v6
         with:
           python-version: '3.14'
           cache: pip
@@ -72,8 +77,8 @@ jobs:
       run:
         working-directory: frontend
     steps:
-      - uses: actions/checkout@v4
-      - uses: actions/setup-node@v4
+      - uses: actions/checkout@v5
+      - uses: actions/setup-node@v5
         with:
           node-version: '20'
           cache: npm
@@ -88,8 +93,8 @@ jobs:
     # code is absent from the bundle - the delete-a-plugin guarantee in CI.
     runs-on: arc-runner-set
     steps:
-      - uses: actions/checkout@v4
-      - uses: actions/setup-node@v4
+      - uses: actions/checkout@v5
+      - uses: actions/setup-node@v5
         with:
           node-version: '20'
           cache: npm