allowed_tools parameter is ignored - all built-in tools are provided despite whitelist

[noahzweben]

Description
The allowed_tools parameter in ClaudeAgentOptions is being ignored. When explicitly setting a whitelist of allowed tools, the SDK still provides all built-in tools to Claude.

[qing-ant]

The root cause of allowed_tools being silently ignored was fixed in PR #638, which addressed #634 (the allowed_tools=[] truthiness bug in _build_command). The fix changed the truthiness check to an is not None check so that both empty lists and populated lists are correctly passed to the CLI subprocess. This fix is available in SDK v0.1.45+. Closing as resolved.