fix(rp-4): use bsdtar fallback for Windows .zip packaging

build-cli-windows job for v0.1.6 (CI run 26521444308) failed at the
'Package zip' step because MSYS `zip` binary is not on PATH in the
windows-latest runner's Git Bash by default.

Use Windows 10+ built-in bsdtar (`tar.exe -a -cf foo.zip ...`)
when available — it auto-detects the archive format from the .zip
extension. Falls back to standalone `zip` when bsdtar is missing
(non-Windows hosts without bsdtar installed).

The tar.gz branch is unaffected; verified locally on GNU tar 1.34:
  FLAVOR=cpu PLATFORM=linux-x86_64 VERSION=0.1.7-prep-smoke ./scripts/package_cli_tarball.sh
  -> 15M tarball produces {"device":"cpu"}.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: zhmiao

sparrow-engine/scripts/package_cli_tarball.sh

@@ -217,9 +217,18 @@ case "$archive_ext" in
     tar -C "$work" -czf "$out_archive_abs" "$bundle_name"
     ;;
   zip)
-    # zip preserves the executable bit on Unix-style tools; Windows users
-    # extract via Explorer or `tar -xf` (Win10+ ships bsdtar).
-    ( cd "$work" && zip -qr "$out_archive_abs" "$bundle_name" )
+    # Prefer bsdtar (built into Windows 10+ as `tar.exe`; cross-platform on
+    # macOS/Linux when available) — it auto-detects the archive format from
+    # the .zip extension and is more portable than MSYS `zip`. Fall back to
+    # the standalone `zip` binary if bsdtar isn't present.
+    if tar --version 2>/dev/null | grep -qi bsdtar; then
+      tar -a -cf "$out_archive_abs" -C "$work" "$bundle_name"
+    elif command -v zip >/dev/null 2>&1; then
+      ( cd "$work" && zip -qr "$out_archive_abs" "$bundle_name" )
+    else
+      echo "ERROR: neither bsdtar nor zip available to create $out_archive_abs" >&2
+      exit 6
+    fi
     ;;
 esac