BLD - Support updating existing GitHub releases

Update the release workflow to check for an existing release tag before creation. If a release is already present, upload the assets using the --clobber flag to ensure the workflow is idempotent and prevents failures on reruns.

.github/workflows/release.yml

@@ -106,10 +106,18 @@ jobs:
       - name: Publish GitHub release
         env:
           GH_TOKEN: ${{ github.token }}
-        run: >-
-          gh release create "$GITHUB_REF_NAME"
-          "sky_phone-${GITHUB_REF_NAME}.zip"
-          "sky_phone-${GITHUB_REF_NAME}.zip.sha256"
-          --verify-tag
-          --generate-notes
-          --title "Sky Phone $GITHUB_REF_NAME"
+        shell: bash
+        run: |
+          set -euo pipefail
+          archive="sky_phone-${GITHUB_REF_NAME}.zip"
+
+          if gh release view "$GITHUB_REF_NAME" >/dev/null 2>&1; then
+            gh release upload "$GITHUB_REF_NAME" "$archive" "${archive}.sha256" --clobber
+          else
+            gh release create "$GITHUB_REF_NAME" \
+              "$archive" \
+              "${archive}.sha256" \
+              --verify-tag \
+              --generate-notes \
+              --title "Sky Phone $GITHUB_REF_NAME"
+          fi