fix(release): contents:write for SBOM asset upload

The sbom job's `permissions: packages: read` replaces the default token
set, so `gh release upload` got 403 Resource not accessible. Grant
contents:write alongside packages:read.

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Co-Authored-By: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>

.github/workflows/release.yml

@@ -327,6 +327,8 @@ jobs:
     runs-on: ubuntu-latest
     permissions:
       packages: read
+      # contents: write — the job uploads SBOM assets onto the release.
+      contents: write
     env:
       VERSION: ${{ needs.verify.outputs.version }}
     steps: