Stream apply_patch changes (#17862)

Adds new events for streaming apply_patch changes from responses api.
This is to enable clients to show progress during file writes.

Caveat: This does not work with apply_patch in function call mode, since
that required adding streaming json parsing.

codex-rs/codex-api/src/common.rs

@@ -80,6 +80,11 @@ pub enum ResponseEvent {
         token_usage: Option<TokenUsage>,
     },
     OutputTextDelta(String),
+    ToolCallInputDelta {
+        item_id: String,
+        call_id: Option<String>,
+        delta: String,
+    },
     ReasoningSummaryDelta {
         delta: String,
         summary_index: i64,