复用 DirectProject 用户输入校验读取的 manifest

让校验返回已读取的 manifest，wire 投影复用同一份数据，避免一次输入重复读取项目清单。

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

@@ -12,7 +12,7 @@ pub(crate) const MAX_DIRECT_CODEX_REFERENCES: usize = 32;
 pub(crate) fn validate_direct_codex_user_item(
     root: &Path,
     item: &DirectCodexUserItem,
-) -> Result<(), String> {
+) -> Result<GameCreationAppManifest, String> {
     let DirectCodexUserItem::Message(message) = item;
     if !matches!(message.role, DirectCodexUserRole::User) {
         return Err("DirectProject 只接受 user message item".to_string());
@@ -45,7 +45,7 @@ pub(crate) fn validate_direct_codex_user_item(
     if reference_count > MAX_DIRECT_CODEX_REFERENCES {
         return Err(format!("一次最多引用 {MAX_DIRECT_CODEX_REFERENCES} 个素材"));
     }
-    Ok(())
+    Ok(manifest)
 }
 
 pub(crate) fn validate_resource_id_and_manifest(

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

@@ -1,6 +1,6 @@
 use super::model::{DirectCodexUserContentPart, DirectCodexUserItem};
 use super::validation::validate_direct_codex_user_item;
-use crate::agent::{read_manifest_for_project, sanitize_attachment_local_path};
+use crate::agent::sanitize_attachment_local_path;
 use serde_json::Value;
 use std::path::Path;
 
@@ -57,8 +57,7 @@ pub(crate) fn direct_codex_user_item_to_wire_input(
     root: &Path,
     item: &DirectCodexUserItem,
 ) -> Result<Value, String> {
-    validate_direct_codex_user_item(root, item)?;
-    let manifest = read_manifest_for_project(root)?;
+    let manifest = validate_direct_codex_user_item(root, item)?;
     let DirectCodexUserItem::Message(message) = item;
     let mut input = Vec::with_capacity(message.content.len());
     for part in &message.content {