chore(ci): opt JS actions into Node 24 ahead of June 2026 default

GitHub deprecated Node 20 as the JavaScript-actions runtime on 2025-09-19
and will force Node 24 as the default starting 2026-06-02. Until then,
the runner emits a deprecation warning for every workflow run that uses
actions/checkout@v4 + actions/setup-node@v4 (i.e., every CI + release
run).

Setting FORCE_JAVASCRIPT_ACTIONS_TO_NODE24=true at the workflow env
level opts in early — silences the warning today and ensures we're on
the runtime GitHub is migrating us to anyway.

Reference: https://github.blog/changelog/2025-09-19-deprecation-of-node-20-on-github-actions-runners/

Applied to both ci.yml and release.yml — the deprecation warning
appears on every job in both workflows.

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

Author: A.R.

.github/workflows/ci.yml

@@ -11,6 +11,10 @@ env:
   # build (70+ entry points + DTS emission). Lift the cap to 4GB; both
   # ubuntu-latest and windows-latest runners have ~7GB RAM available.
   NODE_OPTIONS: "--max-old-space-size=4096"
+  # Opt into Node 24 for GitHub-shipped JS actions (checkout, setup-node, …)
+  # ahead of the June 2nd 2026 default. Silences the deprecation warning and
+  # ensures we're on the runtime GitHub is migrating to.
+  FORCE_JAVASCRIPT_ACTIONS_TO_NODE24: "true"
 
 jobs:
   build-and-test:

.github/workflows/release.yml

@@ -23,6 +23,10 @@ env:
   # tsup's --dts worker hits Node's default ~2GB heap during the mcp-server
   # build (70+ entry points + DTS emission). Lift the cap to 4GB.
   NODE_OPTIONS: "--max-old-space-size=4096"
+  # Opt into Node 24 for GitHub-shipped JS actions (checkout, setup-node, …)
+  # ahead of the June 2nd 2026 default. Silences the deprecation warning and
+  # ensures we're on the runtime GitHub is migrating to.
+  FORCE_JAVASCRIPT_ACTIONS_TO_NODE24: "true"
 
 permissions:
   contents: write