ci: force Node.js 24 for JS actions (deadline June 2, 2026)

Add FORCE_JAVASCRIPT_ACTIONS_TO_NODE24=true env var to ci.yml,
security.yml and build-kiosk.yml to prevent action failures when
GitHub removes Node 20 runner support on 2026-06-02.

Also re-triggers CI to bypass transient 403 infrastructure failure
that hit the previous run (GitHub CDN outage).

.github/workflows/build-kiosk.yml

@@ -1,5 +1,8 @@
 name: Build & Release Kiosk APK
 
+env:
+  FORCE_JAVASCRIPT_ACTIONS_TO_NODE24: true
+
 on:
   push:
     branches: [main]

.github/workflows/ci.yml

@@ -6,6 +6,9 @@ on:
   pull_request:
     branches: [main]
 
+env:
+  FORCE_JAVASCRIPT_ACTIONS_TO_NODE24: true
+
 jobs:
   lint-php:
     name: PHP Syntax Check

.github/workflows/security.yml

@@ -1,5 +1,8 @@
 name: Security Scan (Trivy)
 
+env:
+  FORCE_JAVASCRIPT_ACTIONS_TO_NODE24: true
+
 on:
   push:
     branches: [main, develop]