Support profiles in agent2 (#36034)

We still need a profile selector.

Release Notes:

- N/A

---------

Co-authored-by: Ben Brandt <benjamin.j.brandt@gmail.com>

crates/agent2/src/tools/now_tool.rs

@@ -47,20 +47,13 @@ impl AgentTool for NowTool {
     fn run(
         self: Arc<Self>,
         input: Self::Input,
-        event_stream: ToolCallEventStream,
+        _event_stream: ToolCallEventStream,
         _cx: &mut App,
     ) -> Task<Result<String>> {
         let now = match input.timezone {
             Timezone::Utc => Utc::now().to_rfc3339(),
             Timezone::Local => Local::now().to_rfc3339(),
         };
-        let content = format!("The current datetime is {now}.");
-
-        event_stream.update_fields(acp::ToolCallUpdateFields {
-            content: Some(vec![content.clone().into()]),
-            ..Default::default()
-        });
-
-        Task::ready(Ok(content))
+        Task::ready(Ok(format!("The current datetime is {now}.")))
     }
 }