修复公开资产授权一致性与签名期限

公开资产 metadata 和作品授权改为在同一 SpacetimeDB 事务快照中判断
移除连接级公开授权订阅缓存对 ACL 的参与
公开读取签名有效期上限固定为 600 秒并保留 owner 和 admin 行为
同步生成 bindings 并更新后端契约与项目记忆

server-rs/crates/module-assets/src/application.rs

@@ -19,6 +19,15 @@ pub struct AssetObjectProcedureResult {
     pub error_message: Option<String>,
 }
 
+#[cfg_attr(feature = "spacetime-types", derive(SpacetimeType))]
+#[derive(Clone, Debug, PartialEq, Eq, Serialize, Deserialize)]
+pub struct AssetObjectReadAccessProcedureResult {
+    pub ok: bool,
+    pub record: Option<AssetObjectUpsertSnapshot>,
+    pub public_work_granted: bool,
+    pub error_message: Option<String>,
+}
+
 #[cfg_attr(feature = "spacetime-types", derive(SpacetimeType))]
 #[derive(Clone, Debug, PartialEq, Eq, Serialize, Deserialize)]
 pub struct AssetHistoryListResult {

server-rs/crates/module-assets/src/lib.rs

@@ -10,7 +10,8 @@ mod asset_object_service;
 
 pub use application::{
     AssetEntityBindingProcedureResult, AssetHistoryListResult, AssetObjectProcedureResult,
-    ConfirmAssetObjectResult, build_asset_entity_binding_input, build_asset_object_upsert_input,
+    AssetObjectReadAccessProcedureResult, ConfirmAssetObjectResult,
+    build_asset_entity_binding_input, build_asset_object_upsert_input,
 };
 #[cfg(feature = "server-service")]
 pub use asset_object_service::{