chore(ci): bump GitHub Actions to Node 24 versions

GitHub forces Node 20 actions to Node 24 on 2026-06-16. Bump to current
node24 runtimes (inputs verified unchanged):
- actions/checkout v4 -> v6
- actions/upload-artifact v4 -> v7
- softprops/action-gh-release v2 -> v3

.github/workflows/block-claude-coauthor.yml

@@ -14,7 +14,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
         with:
           fetch-depth: 0
 

.github/workflows/ci.yml

@@ -9,7 +9,7 @@ jobs:
   semgrep:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
 
       - name: Install Semgrep
         run: pip install semgrep

.github/workflows/release-menubar.yml

@@ -23,7 +23,7 @@ jobs:
     runs-on: macos-latest
     steps:
       - name: Checkout
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
 
       - name: Resolve version label
         id: version
@@ -42,7 +42,7 @@ jobs:
 
       - name: Upload artifact (for manual runs)
         if: github.event_name == 'workflow_dispatch'
-        uses: actions/upload-artifact@v4
+        uses: actions/upload-artifact@v7
         with:
           name: CodeBurnMenubar-${{ steps.version.outputs.value }}
           path: |
@@ -52,7 +52,7 @@ jobs:
 
       - name: Create / update GitHub Release
         if: startsWith(github.ref, 'refs/tags/mac-v')
-        uses: softprops/action-gh-release@v2
+        uses: softprops/action-gh-release@v3
         with:
           tag_name: ${{ github.ref_name }}
           name: Menubar ${{ steps.version.outputs.value }}