Update sanitization logic in mcp.py

[Redamency]

Change sanitization logic to prepend 'mcp_' and keep last 60 characters.

When we connect mcp server by sse,server_id is always equals server_url, our tool_name like this

tool_name = f"mcp_{server_id}_{original_name}"

Because server_id contains both url and key, its length is always greater than 64, so all tool_name are the same

self.tool_map[tool_name] = server_tool

Resulting in only the last tool being saved, while the others are overwritten