Centralize always_allow logic when authorizing agent2 tools (#35988)

Release Notes:

- N/A

---------

Co-authored-by: Cole Miller <cole@zed.dev>
Co-authored-by: Bennet Bo Fenner <bennetbo@gmx.de>
Co-authored-by: Agus Zubiaga <agus@zed.dev>
Co-authored-by: Ben Brandt <benjamin.j.brandt@gmail.com>

crates/agent2/src/tests/test_tools.rs

@@ -110,9 +110,9 @@ impl AgentTool for ToolRequiringPermission {
         event_stream: ToolCallEventStream,
         cx: &mut App,
     ) -> Task<Result<String>> {
-        let auth_check = event_stream.authorize("Authorize?".into());
+        let authorize = event_stream.authorize("Authorize?", cx);
         cx.foreground_executor().spawn(async move {
-            auth_check.await?;
+            authorize.await?;
             Ok("Allowed".to_string())
         })
     }