Expose structured standalone web search results (#32898)

## Why

Standalone web search can return structured result DTOs separately from its
model-facing text output. App-server clients need access to that data without
coupling Codex to every result type or field.

## What changed

- Preserve the optional `results` array from `/v1/alpha/search` as opaque JSON
  through web-search completion events, thread history, and app-server
  `webSearch` items.
- Keep responses from older endpoints compatible when `results` is absent, and
  allow clients to ignore result types and fields they do not understand.
- Regenerate the protocol schemas and TypeScript definitions for the optional
  field.

## Testing

- Cover responses with missing, empty, and forward-compatible result payloads.
- Verify standalone web-search results round-trip through app-server item
  notifications and thread-item conversion.

GitOrigin-RevId: 739ef5694ece5733f7b8749ec41d6bfa3f33c8c5

codex-rs/app-server-protocol/src/protocol/thread_history.rs

@@ -634,6 +634,7 @@ impl ThreadHistoryBuilder {
             id: payload.call_id.clone(),
             query: String::new(),
             action: None,
+            results: None,
         });
         self.upsert_item_in_current_turn(item);
     }
@@ -643,6 +644,7 @@ impl ThreadHistoryBuilder {
             id: payload.call_id.clone(),
             query: payload.query.clone(),
             action: Some(web_search_action_from_core(payload.action.clone())),
+            results: payload.results.clone(),
         });
         self.upsert_item_in_current_turn(item);
     }
@@ -2664,6 +2666,11 @@ mod tests {
                     query: Some("codex".into()),
                     queries: None,
                 },
+                results: Some(vec![serde_json::json!({
+                    "type": "text_result",
+                    "ref_id": "turn0search0",
+                    "url": "https://example.com/codex",
+                })]),
             }),
             EventMsg::ExecCommandEnd(ExecCommandEndEvent {
                 call_id: "exec-1".into(),
@@ -2720,6 +2727,11 @@ mod tests {
                     query: Some("codex".into()),
                     queries: None,
                 }),
+                results: Some(vec![serde_json::json!({
+                    "type": "text_result",
+                    "ref_id": "turn0search0",
+                    "url": "https://example.com/codex",
+                })]),
             })
         );
         assert_eq!(
@@ -4195,6 +4207,7 @@ mod tests {
                     query: Some("codex".into()),
                     queries: None,
                 },
+                results: None,
             }),
         ));
         assert_eq!(
@@ -4209,6 +4222,7 @@ mod tests {
                             query: Some("codex".into()),
                             queries: None,
                         }),
+                        results: None,
                     }),
                 }],
                 changed_turns: Vec::new(),
@@ -4330,6 +4344,7 @@ mod tests {
                     query: Some("codex".into()),
                     queries: None,
                 },
+                results: None,
             })),
         ]);
         assert_eq!(
@@ -4344,6 +4359,7 @@ mod tests {
                             query: Some("codex".into()),
                             queries: None,
                         }),
+                        results: None,
                     }),
                 }],
                 changed_turns: vec![ThreadHistoryTurnChange {

codex-rs/app-server-protocol/src/protocol/v2/item.rs

@@ -902,6 +902,7 @@ impl From<CoreTurnItem> for ThreadItem {
                 id: search.id,
                 query: search.query,
                 action: Some(web_search_action_from_core(search.action)),
+                results: search.results,
             }),
             CoreTurnItem::ImageView(image) => ThreadItem::ImageView {
                 id: image.id,

codex-rs/app-server-protocol/src/protocol/v2/tests.rs

@@ -2777,6 +2777,11 @@ fn core_turn_item_into_thread_item_converts_supported_variants() {
             query: Some("docs".to_string()),
             queries: None,
         },
+        results: Some(vec![serde_json::json!({
+            "type": "text_result",
+            "ref_id": "turn0search0",
+            "url": "https://example.com/docs",
+        })]),
     });
 
     let expected_search_item = WebSearchItem {
@@ -2786,6 +2791,11 @@ fn core_turn_item_into_thread_item_converts_supported_variants() {
             query: Some("docs".to_string()),
             queries: None,
         }),
+        results: Some(vec![serde_json::json!({
+            "type": "text_result",
+            "ref_id": "turn0search0",
+            "url": "https://example.com/docs",
+        })]),
     };
 
     assert_eq!(