Ensure context servers are spawned in the workspace directory (#35271)

This fixes an issue where we were not setting the context server working
directory at all.

Release Notes:

- Context servers will now be spawned in the currently active project
root.

---------

Co-authored-by: Danilo Leal <danilo@zed.dev>

crates/agent_servers/src/codex.rs

@@ -47,6 +47,7 @@ impl AgentServer for Codex {
         cx: &mut App,
     ) -> Task<Result<Rc<dyn AgentConnection>>> {
         let project = project.clone();
+        let working_directory = project.read(cx).active_project_directory(cx);
         cx.spawn(async move |cx| {
             let settings = cx.read_global(|settings: &SettingsStore, _| {
                 settings.get::<AllAgentServersSettings>(None).codex.clone()
@@ -65,6 +66,7 @@ impl AgentServer for Codex {
                     args: command.args,
                     env: command.env,
                 },
+                working_directory,
             )
             .into();
             ContextServer::start(client.clone(), cx).await?;