fix(anthropic): avoid sanitized tool id collisions

nanobot/providers/anthropic_provider.py

@@ -3,6 +3,7 @@
 from __future__ import annotations
 
 import asyncio
+import hashlib
 import re
 import secrets
 import string
@@ -37,7 +38,9 @@ def _sanitize_tool_id(tid: str) -> str:
     """
     if not tid or _VALID_TOOL_ID.match(tid):
         return tid
-    return re.sub(r"[^a-zA-Z0-9_-]", "_", tid)
+    safe_prefix = re.sub(r"[^a-zA-Z0-9_-]", "_", tid)[:48].strip("_") or "toolu"
+    digest = hashlib.sha1(tid.encode()).hexdigest()[:8]
+    return f"{safe_prefix}_{digest}"
 
 
 class AnthropicProvider(LLMProvider):