Normalize shell and patch tool cards

server/src/session/driver.rs

@@ -389,6 +389,15 @@ pub enum Event {
     },
 }
 
+/// The common presentation of a file change, whichever driver produced it.
+pub(super) fn patch_start(id: String, diff: String) -> Event {
+    Event::ToolStart {
+        id,
+        tool: "Patch".to_string(),
+        input: serde_json::json!({"diff": diff}),
+    }
+}
+
 /// How much the model was holding, from the three figures a turn reports:
 /// the input side only, prompt plus both cache figures. A cached token is
 /// cheaper but it is still one the model was given; output is what the turn