compaction (#10034)

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codex-rs/protocol/src/items.rs

@@ -2,6 +2,7 @@ use crate::models::WebSearchAction;
 use crate::protocol::AgentMessageEvent;
 use crate::protocol::AgentReasoningEvent;
 use crate::protocol::AgentReasoningRawContentEvent;
+use crate::protocol::ContextCompactedEvent;
 use crate::protocol::EventMsg;
 use crate::protocol::UserMessageEvent;
 use crate::protocol::WebSearchEndEvent;
@@ -21,6 +22,7 @@ pub enum TurnItem {
     AgentMessage(AgentMessageItem),
     Reasoning(ReasoningItem),
     WebSearch(WebSearchItem),
+    ContextCompaction(ContextCompactionItem),
 }
 
 #[derive(Debug, Clone, Deserialize, Serialize, TS, JsonSchema)]
@@ -57,6 +59,29 @@ pub struct WebSearchItem {
     pub action: WebSearchAction,
 }
 
+#[derive(Debug, Clone, Deserialize, Serialize, TS, JsonSchema)]
+pub struct ContextCompactionItem {
+    pub id: String,
+}
+
+impl ContextCompactionItem {
+    pub fn new() -> Self {
+        Self {
+            id: uuid::Uuid::new_v4().to_string(),
+        }
+    }
+
+    pub fn as_legacy_event(&self) -> EventMsg {
+        EventMsg::ContextCompacted(ContextCompactedEvent {})
+    }
+}
+
+impl Default for ContextCompactionItem {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
 impl UserMessageItem {
     pub fn new(content: &[UserInput]) -> Self {
         Self {
@@ -195,6 +220,7 @@ impl TurnItem {
             TurnItem::AgentMessage(item) => item.id.clone(),
             TurnItem::Reasoning(item) => item.id.clone(),
             TurnItem::WebSearch(item) => item.id.clone(),
+            TurnItem::ContextCompaction(item) => item.id.clone(),
         }
     }
 
@@ -204,6 +230,7 @@ impl TurnItem {
             TurnItem::AgentMessage(item) => item.as_legacy_events(),
             TurnItem::WebSearch(item) => vec![item.as_legacy_event()],
             TurnItem::Reasoning(item) => item.as_legacy_events(show_raw_agent_reasoning),
+            TurnItem::ContextCompaction(item) => vec![item.as_legacy_event()],
         }
     }
 }