fix: set max_tool_iterations=10 in test build_agent

Fix agent_respects_max_tool_iterations test by explicitly setting
max_tool_iterations to 10 in build_agent helper function.

The default value was changed from 10 to 25, causing this test to fail
as it expected the limit to be 10 iterations.

Author: louisdevzz

tests/agent_loop_robustness.rs

@@ -199,13 +199,18 @@ fn tool_response(calls: Vec<ToolCall>) -> ChatResponse {
 }
 
 fn build_agent(provider: Box<dyn Provider>, tools: Vec<Box<dyn Tool>>) -> Agent {
+    use zerobuild::config::AgentConfig;
     Agent::builder()
         .provider(provider)
         .tools(tools)
         .memory(make_memory())
         .observer(make_observer())
         .tool_dispatcher(Box::new(NativeToolDispatcher))
         .workspace_dir(std::env::temp_dir())
+        .config(AgentConfig {
+            max_tool_iterations: 10,
+            ..AgentConfig::default()
+        })
         .build()
         .unwrap()
 }