refactor: 大规模模块拆分与代码精简，新增 ai-pipeline/data-contracts 独立 crate

- 新增 aether-ai-pipeline 和 aether-data-contracts crate，将 pipeline 逻辑与数据契约从 gateway 中解耦
- 重构 admin handlers：拆分单体模块为 auth/billing/endpoint/features/model/observability/provider/system 等独立子模块
- 合并 chat/cli 重复代码路径：精简 conversion、finalize、planner 中的 sync/chat/cli 分支
- 重构 scheduler/executor/data 层，引入 facade 模式降低模块间耦合
- 移除冗余的 intent 模块，将 plan_fallback/policy/stream_path/sync_path 迁移至 executor
- 前端适配：调整 admin API 调用和 provider 模型测试对话框

apps/aether-gateway/src/state/runtime/billing/finance_queries.rs

@@ -5,10 +5,9 @@ use aether_data::repository::wallet::{
     StoredAdminWalletRefundRequestItem, StoredAdminWalletTransaction,
 };
 
-use crate::state::AdminPaymentCallbackRecord;
 use crate::{
     AdminWalletMutationOutcome, AdminWalletPaymentOrderRecord, AdminWalletRefundRecord, AppState,
-    GatewayError,
+    GatewayAdminPaymentCallbackView, GatewayError,
 };
 
 impl AppState {
@@ -124,7 +123,7 @@ impl AppState {
         payment_method: Option<&str>,
         limit: usize,
         offset: usize,
-    ) -> Result<Option<(Vec<AdminPaymentCallbackRecord>, u64)>, GatewayError> {
+    ) -> Result<Option<(Vec<GatewayAdminPaymentCallbackView>, u64)>, GatewayError> {
         #[cfg(test)]
         if let Some(store) = self.admin_payment_callback_store.as_ref() {
             let mut items = store
@@ -147,6 +146,7 @@ impl AppState {
                 .into_iter()
                 .skip(offset)
                 .take(limit)
+                .map(Into::into)
                 .collect::<Vec<_>>();
             return Ok(Some((items, total)));
         }
@@ -160,6 +160,7 @@ impl AppState {
             page.items
                 .into_iter()
                 .map(stored_admin_payment_callback_to_gateway)
+                .map(Into::into)
                 .collect(),
             page.total,
         )))
@@ -415,8 +416,8 @@ fn stored_admin_payment_order_to_gateway(
 
 fn stored_admin_payment_callback_to_gateway(
     record: StoredAdminPaymentCallback,
-) -> AdminPaymentCallbackRecord {
-    AdminPaymentCallbackRecord {
+) -> GatewayAdminPaymentCallbackView {
+    GatewayAdminPaymentCallbackView {
         id: record.id,
         payment_order_id: record.payment_order_id,
         payment_method: record.payment_method,