Normalize shell and patch tool cards

server/src/session/echo.rs

@@ -10,6 +10,8 @@
 //! - `/tool [input]` -- a full tool run, start through end.
 //! - `/bash [command]` -- a Bash call carrying that command, for what the
 //!   phone's shell highlighting does to a particular line.
+//! - `/patch` -- one common patch call, for the diff presentation shared by
+//!   real Codex and Claude sessions.
 //! - `/tools [n] [gap]` -- n calls back to back. `gap` is seconds between one
 //!   call and the next, which is what makes a run *grow* while somebody is
 //!   looking at it -- the only way to reach the state where a call opened on
@@ -73,7 +75,7 @@ use std::sync::{Arc, Mutex};
 use std::time::Duration;
 
 use super::driver::{
-    AttachmentRef, Driver, Event, EventSink, QuestionOption, SessionStatus, Unqueued,
+    AttachmentRef, Driver, Event, EventSink, QuestionOption, SessionStatus, Unqueued, patch_start,
 };
 use super::subagent::Subagents;
 
@@ -621,6 +623,7 @@ impl EchoDriver {
         let run_bash = text
             .strip_prefix("/bash")
             .map(|rest| rest.trim().to_string());
+        let run_patch = text == "/patch";
         // Seconds to stay running before answering, default 30. Clamped rather
         // than trusted: a session pinned running for an hour by a typo is a
         // worse outcome than a short wait.
@@ -790,6 +793,20 @@ impl EchoDriver {
                 });
             }
 
+            if run_patch {
+                let id = format!("p-{}", super::random_hex());
+                send(patch_start(
+                    id.clone(),
+                    "--- src/example.rs\n+++ src/example.rs\n@@ -1,3 +1,3 @@\n fn answer() -> u8 {\n-    41\n+    42\n }\n"
+                        .to_string(),
+                ));
+                tokio::time::sleep(DELTA_DELAY).await;
+                send(Event::ToolEnd {
+                    id,
+                    output: String::new(),
+                });
+            }
+
             if let Some(input) = run_tool {
                 let id = format!("t-{}", super::random_hex());
                 send(Event::ToolStart {