fix: include client_tools in streaming requires_approval_tools (#8230)

When streaming, the LLM adapter needs to know which tools require
approval so it can emit ApprovalRequestMessage instead of ToolCallMessage.
Client-side tools were being passed to the agent but not included in
the requires_approval_tools list passed to the streaming interface.

This caused the streaming interface to emit tool_call_message for
client tools, but the stop_reason was still requires_approval,
resulting in empty approvals arrays on the client side.

🤖 Generated with [Letta Code](https://letta.com)

Co-authored-by: Letta <noreply@letta.com>

letta/agents/letta_agent_v3.py

@@ -669,7 +669,8 @@ class LettaAgentV3(LettaAgentV2):
                             use_assistant_message=False,  # NOTE: set to false
                             requires_approval_tools=self.tool_rules_solver.get_requires_approval_tools(
                                 set([t["name"] for t in valid_tools])
-                            ),
+                            )
+                            + [ct.name for ct in self.client_tools],
                             step_id=step_id,
                             actor=self.actor,
                         )