Bump GitHub Actions to v5 (Node.js 24)

actions/checkout@v4 and actions/upload-artifact@v4 use the
deprecated Node.js 20 runtime. v5 uses Node.js 24.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: pnc

.github/workflows/ci.yml

@@ -11,7 +11,7 @@ jobs:
   unit-tests:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v5
       - name: Install uv
         run: |
           curl -fL https://github.com/astral-sh/uv/releases/latest/download/uv-x86_64-unknown-linux-gnu.tar.gz \
@@ -22,7 +22,7 @@ jobs:
     runs-on: ubuntu-latest
     timeout-minutes: 20
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v5
       - name: Install uv
         run: |
           curl -fL https://github.com/astral-sh/uv/releases/latest/download/uv-x86_64-unknown-linux-gnu.tar.gz \
@@ -44,7 +44,7 @@ jobs:
 
       - name: Upload logs on failure
         if: failure()
-        uses: actions/upload-artifact@v4
+        uses: actions/upload-artifact@v5
         with:
           name: e2e-linux-logs
           path: |
@@ -55,7 +55,7 @@ jobs:
     runs-on: macos-latest
     timeout-minutes: 20
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v5
       - name: Install uv
         run: |
           curl -fL https://github.com/astral-sh/uv/releases/latest/download/uv-aarch64-apple-darwin.tar.gz \
@@ -72,7 +72,7 @@ jobs:
 
       - name: Upload logs on failure
         if: failure()
-        uses: actions/upload-artifact@v4
+        uses: actions/upload-artifact@v5
         with:
           name: e2e-macos-logs
           path: |