原子化Direct线程与历史回放判定

让thread_for在同一锁内返回线程是否新建。

仅新建Direct线程时读取project.jsonl并注入历史。

保持已有线程只发送当前用户消息。

apps/ai-game-creator-shell/src-tauri/src/agent/codex_app_server.rs

@@ -1417,11 +1417,6 @@ fn trust_isolated_game_creator_codex_workspace(
 }
 
 impl CodexAppServerConnection {
-    async fn has_thread_for(&self, snapshot: &AgentRuntimeProviderRequestSnapshot) -> bool {
-        let key = CodexNodeThreadKey::from(snapshot);
-        self.inner.threads.lock().await.contains_key(&key)
-    }
-
     async fn acquire(
         snapshot: &AgentRuntimeProviderRequestSnapshot,
         llm: &GameCreatorLlmConfig,
@@ -1948,17 +1943,23 @@ impl CodexAppServerConnection {
         snapshot: &AgentRuntimeProviderRequestSnapshot,
         request: &LlmRunRequest,
         llm: &GameCreatorLlmConfig,
-    ) -> Result<CodexThreadLease, platform_llm::LlmError> {
+    ) -> Result<(CodexThreadLease, bool), platform_llm::LlmError> {
         let key = CodexNodeThreadKey::from(snapshot);
         let mut threads = self.inner.threads.lock().await;
+        // The caller holds `turn_gate` while invoking this method. Returning
+        // the creation bit from the same threads lock keeps the replay
+        // decision atomic with thread reuse/creation.
         if let Some(entry) = threads.get_mut(&key) {
             entry.active_uses = entry.active_uses.saturating_add(1);
             entry.last_used = next_game_creator_codex_app_server_usage_tick();
-            return Ok(CodexThreadLease {
-                connection: self.clone(),
-                key,
-                thread_id: entry.thread_id.clone(),
-            });
+            return Ok((
+                CodexThreadLease {
+                    connection: self.clone(),
+                    key,
+                    thread_id: entry.thread_id.clone(),
+                },
+                false,
+            ));
         }
         if threads.len() >= GAME_CREATOR_CODEX_APP_SERVER_THREAD_MAX {
             let evict_key = threads
@@ -2020,11 +2021,14 @@ impl CodexAppServerConnection {
                 active_uses: 1,
             },
         );
-        Ok(CodexThreadLease {
-            connection: self.clone(),
-            key,
-            thread_id,
-        })
+        Ok((
+            CodexThreadLease {
+                connection: self.clone(),
+                key,
+                thread_id,
+            },
+            true,
+        ))
     }
 
     async fn register_turn(&self, turn_id: &str) -> mpsc::UnboundedReceiver<CodexTurnEvent> {
@@ -2075,6 +2079,7 @@ impl CodexAppServerConnection {
             snapshot,
             llm,
             request,
+            None,
             on_agent_message_delta,
             None,
             None,
@@ -2087,14 +2092,37 @@ impl CodexAppServerConnection {
         snapshot: &AgentRuntimeProviderRequestSnapshot,
         llm: &GameCreatorLlmConfig,
         request: LlmRunRequest,
+        direct_client_turn_id: Option<&str>,
         mut on_agent_message_delta: Option<&mut (dyn FnMut(&platform_llm::LlmStreamDelta) + Send)>,
         mut direct_observer: Option<&mut (dyn FnMut(DirectCodexTurnObservation) + Send)>,
         mut audit: Option<&mut DirectCodexTurnAudit>,
     ) -> Result<platform_llm::LlmRunResponse, platform_llm::LlmError> {
         let _turn_guard = self.inner.turn_gate.lock().await;
-        let thread_lease = self.thread_for(snapshot, &request, llm).await?;
+        let (thread_lease, thread_created) = self.thread_for(snapshot, &request, llm).await?;
         self.wait_for_initial_client_mcp_startup().await;
         let thread_id = thread_lease.thread_id.clone();
+        let mut request = request;
+        if thread_created && self.inner.workspace_mode.uses_direct_conversation() {
+            // DirectProject intentionally replays the complete append-only
+            // project history.  AGC owns that durable fact source; keeping
+            // the replay lossless is the product contract even though a
+            // future context-budget policy may need to change this choice.
+            let current_prompt = direct_codex_current_user_prompt(&request).to_string();
+            let history_prompt = build_direct_codex_history_prompt(
+                &self.inner.workspace_path,
+                direct_client_turn_id.unwrap_or("__none__"),
+                &current_prompt,
+            )
+            .map_err(platform_llm::LlmError::InvalidRequest)?;
+            if let Some(message) = request
+                .messages
+                .iter_mut()
+                .rev()
+                .find(|message| message.role == LlmMessageRole::User)
+            {
+                message.content = history_prompt;
+            }
+        }
         let prompt = if self.inner.workspace_mode.uses_direct_conversation() {
             direct_codex_user_prompt(&request)
         } else {
@@ -3145,22 +3173,21 @@ pub(crate) async fn direct_game_creator_codex_chat_at_with_optional_observer(
     )
     .await
     .map_err(|error| error.to_string())?;
-    let user_prompt = if connection.has_thread_for(&snapshot).await {
-        user_prompt
-    } else {
-        build_direct_codex_history_prompt(
-            &codex_root,
-            client_turn_id.unwrap_or("__none__"),
-            &user_prompt,
-        )?
-    };
     let request = LlmRunRequest::single_turn(system_prompt, user_prompt)
         .with_api_kind(api_kind)
         .with_model(config.llm.model.clone())
         .with_request_timeout_ms(config.llm.request_timeout_ms)
         .with_max_output_tokens(16_000);
     connection
-        .run_turn_with_direct_observer(&snapshot, &config.llm, request, None, observer, audit)
+        .run_turn_with_direct_observer(
+            &snapshot,
+            &config.llm,
+            request,
+            client_turn_id,
+            None,
+            observer,
+            audit,
+        )
         .await
         .map(|value| value.text)
         .map_err(|error| error.to_string())
@@ -3173,6 +3200,9 @@ pub(crate) fn build_direct_codex_history_prompt(
 ) -> Result<String, String> {
     let conversation = read_local_conversation_for_session_at(root, None, None)?;
     let current_message_id = format!("direct-codex:{client_turn_id}:user");
+    // The deliberately simple role-prefix format is part of the Direct
+    // replay contract.  Do not introduce an envelope or implicit escaping
+    // here without updating the persisted-history compatibility decision.
     let mut lines = conversation
         .messages
         .iter()
@@ -4622,6 +4652,7 @@ while IFS= read -r line; do :; done
                 &test_snapshot(),
                 &llm,
                 tool_request(),
+                None,
                 Some(&mut on_delta),
                 Some(&mut observer),
                 None,