fix(kernel,desktop): Core Chain Hardening 穷尽审计 7 项修复

审计发现 1 CRITICAL + 4 HIGH + 4 MEDIUM + 4 LOW, 修复如下:

CRITICAL:
- TS seam 测试改为 JSON round-trip 验证 (12 测试覆盖 10 事件类型)

HIGH:
- post_conversation_hook 拦截路径 driver=None 加 debug 日志
- schedule intercept channel send 失败回退 LLM (return Ok(None))

MEDIUM:
- DeltaBuffer.flush() 先 mutation 再 clear, 防止异常丢数据
- ModelsAPI.tsx 去重: 改用 model-config.ts 导出 (消除 2 函数+1 接口+2 常量)
- boot_with_driver docstring 记录跳过 agent 恢复

TypeScript 0 错误, Rust 76 kernel 测试通过, TS 12 seam 测试通过

desktop/src-tauri/src/kernel_commands/chat.rs

@@ -380,6 +380,9 @@ pub async fn agent_chat_stream(
                         let hb = hb_state.clone();
                         let rf = rf_state.clone();
                         let driver = llm_driver.clone();
+                        if driver.is_none() {
+                            tracing::debug!("[agent_chat_stream] Post-hook firing without LLM driver (schedule intercept path)");
+                        }
                         tokio::spawn(async move {
                             crate::intelligence_hooks::post_conversation_hook(
                                 &agent_id_hook, &message_hook, &hb, &rf, driver,