feat: Add validation for macOS installer entries and enhance error handling in release creation script

build/scripts/create_release.sh

@@ -59,6 +59,58 @@ for artifact in data["artifacts"]:
 PY
 )
 
+VALIDATION_RESULT=$(python3 - "$LOCAL_DATA_OUTPUT" "$LOCAL_MANIFEST_OUTPUT" <<'PY'
+import json
+import sys
+from pathlib import Path
+
+data = json.loads(Path(sys.argv[1]).read_text(encoding="utf-8"))
+manifest = json.loads(Path(sys.argv[2]).read_text(encoding="utf-8"))
+
+selected_brands = data.get("brands", [])
+manifest_brands = manifest.get("brands", {})
+missing = []
+
+for brand_id in selected_brands:
+    platform_entry = manifest_brands.get(brand_id, {}).get("macos-universal", {})
+    installer_name = platform_entry.get("installer", "")
+    if not installer_name:
+        missing.append(brand_id)
+
+if missing:
+    print("MISSING:" + ",".join(missing))
+else:
+    print("OK")
+PY
+)
+
+if [[ "$VALIDATION_RESULT" == MISSING:* ]]; then
+    MISSING_BRANDS="${VALIDATION_RESULT#MISSING:}"
+    echo "ERROR: release-manifest.json is missing macos-universal installer entries for brand(s): $MISSING_BRANDS"
+    echo "Build the missing brand(s) first or check artifact naming/version before creating the release."
+    exit 1
+fi
+
+if [ ${#BRANDS[@]} -gt 0 ]; then
+    FOUND_BRANDS_CSV=$(python3 - "$LOCAL_DATA_OUTPUT" <<'PY'
+import json
+import sys
+from pathlib import Path
+
+data = json.loads(Path(sys.argv[1]).read_text(encoding="utf-8"))
+print(",".join(data.get("brands", [])))
+PY
+)
+
+for REQUESTED_BRAND in "${BRANDS[@]}"; do
+    if [[ ",$FOUND_BRANDS_CSV," != *",$REQUESTED_BRAND,"* ]]; then
+        echo "ERROR: Requested brand '$REQUESTED_BRAND' has no local macOS artifact for version $VERSION"
+        echo "Run build/scripts/build_macos.sh --brand $REQUESTED_BRAND first, then retry release creation."
+        exit 1
+    fi
+done
+fi
+
 for ARTIFACT in "${ARTIFACTS[@]}"; do
     if [ -f "$ARTIFACT" ] && [ "${ARTIFACT##*.}" = "dmg" ]; then
         DMG_SIZE=$(du -m "$ARTIFACT" | cut -f1)