feat(ci): add DuckDB binary upload to GitHub Actions workflow

.github/workflows/build-linux-amd64.yml

@@ -189,3 +189,18 @@ jobs:
             --retry 2 --retry-delay 2 --max-time 300 \
             --upload-file "$file" "$url"
           echo "Upload complete."
+          # Also upload the DuckDB shell binary
+          bin_path="./build/release/duckdb"
+          if [ ! -f "$bin_path" ]; then
+            echo "duckdb binary not found at $bin_path" >&2
+            exit 1
+          fi
+          bin_name="$(basename "$bin_path")"
+          bin_url="$server/api/packages/$owner/generic/$pkg/$version/$bin_name?replace=1"
+          echo "Uploading $bin_path to $bin_url"
+          curl -fS -L -X PUT \
+            -u "$auth_user:${GITEA_TOKEN}" \
+            -H "Content-Type: application/octet-stream" \
+            --retry 2 --retry-delay 2 --max-time 300 \
+            --upload-file "$bin_path" "$bin_url"
+          echo "DuckDB binary upload complete."