ACP champagne (#35609)

cherry pick changes from #35510 onto latest main

Release Notes:

- N/A

---------

Co-authored-by: Nathan Sobo <nathan@zed.dev>
Co-authored-by: Antonio Scandurra <me@as-cii.com>
Co-authored-by: Lukas Wirth <lukas@zed.dev>

crates/agent2/src/agent2.rs

@@ -0,0 +1,13 @@
+mod agent;
+mod native_agent_server;
+mod prompts;
+mod templates;
+mod thread;
+mod tools;
+
+#[cfg(test)]
+mod tests;
+
+pub use agent::*;
+pub use native_agent_server::NativeAgentServer;
+pub use thread::*;