chore(deps): bump actions/setup-node from 4 to 6

Bumps [actions/setup-node](https://github.com/actions/setup-node) from 4 to 6.
- [Release notes](https://github.com/actions/setup-node/releases)
- [Commits](actions/setup-node@v4...v6)

---
updated-dependencies:
- dependency-name: actions/setup-node
  dependency-version: '6'
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

.github/workflows/ci.yml

@@ -32,7 +32,7 @@ jobs:
     steps:
       - uses: actions/checkout@v5
       - name: Set up Node.js
-        uses: actions/setup-node@v4
+        uses: actions/setup-node@v6
         with:
           node-version: "20"
       - name: Install pnpm
@@ -66,7 +66,7 @@ jobs:
     steps:
       - uses: actions/checkout@v4
       - name: Set up Node.js
-        uses: actions/setup-node@v4
+        uses: actions/setup-node@v6
         with:
           node-version: "20"
       - name: Install pnpm
@@ -94,7 +94,7 @@ jobs:
       - name: Install uv
         run: curl -LsSf https://astral.sh/uv/install.sh | sh
       - name: Set up Node.js
-        uses: actions/setup-node@v4
+        uses: actions/setup-node@v6
         with:
           node-version: "20"
       - name: Install pnpm