feat: Add format_bytes utility to formatting module

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

.openclaw/agents/core/formatting.py

@@ -198,6 +198,23 @@ def truncate(text: str, max_length: int = 100, suffix: str = "...") -> str:
     return text[:max_length - len(suffix)] + suffix
 
 
+def format_bytes(size_bytes: int) -> str:
+    """
+    Format byte size to human-readable string.
+
+    Args:
+        size_bytes: Size in bytes
+
+    Returns:
+        Formatted string (e.g., "1.5 MB")
+    """
+    for unit in ['B', 'KB', 'MB', 'GB', 'TB']:
+        if size_bytes < 1024.0:
+            return f"{size_bytes:.1f} {unit}"
+        size_bytes /= 1024.0
+    return f"{size_bytes:.1f} PB"
+
+
 __all__ = [
     "clean_output",
     "format_response",
@@ -206,5 +223,6 @@ __all__ = [
     "format_conversation_message",
     "format_status",
     "pretty_print_json",
-    "truncate"
+    "truncate",
+    "format_bytes"
 ]