feat(skills/settings): 技能复制 + 设置持久化等会话前改动

- 技能复制:新增 POST 复制接口(_rewrite_skill_frontmatter_name 重写 frontmatter name + 校验 + 去重),前端 skills api/hooks 与技能设置页配套
- 设置持久化:lastAgentId、线程 RAG 模式锁(settings/index、local)
- i18n(en/zh/types)、agent-card/input-box/message-list 等页面文案与交互微调
- scheduler/element.py 小修

(本批为会话前已存在的工作区改动,按要求一并提交;构建产物 backend.zip 未提交)

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

frontend-web/src/core/i18n/locales/en-US.ts

@@ -41,6 +41,7 @@ export const enUS: Translations = {
     code: "Code",
     preview: "Preview",
     cancel: "Cancel",
+    confirm: "Confirm",
     save: "Save",
     install: "Install",
     create: "Create",
@@ -80,6 +81,7 @@ export const enUS: Translations = {
   // Input Box
   inputBox: {
     placeholder: "How can I assist you today?",
+    editQuestion: "Edit question",
     createSkillPrompt:
       "We're going to build a new skill step by step with `skill-creator`. To start, what do you want this skill to do?",
     addAttachments: "Add attachments",

frontend-web/src/core/i18n/locales/types.ts

@@ -42,6 +42,7 @@ export interface Translations {
     code: string;
     preview: string;
     cancel: string;
+    confirm: string;
     save: string;
     install: string;
     create: string;
@@ -77,6 +78,7 @@ export interface Translations {
   // Input Box
   inputBox: {
     placeholder: string;
+    editQuestion: string;
     createSkillPrompt: string;
     addAttachments: string;
     mode: string;

frontend-web/src/core/i18n/locales/zh-CN.ts

@@ -41,6 +41,7 @@ export const zhCN: Translations = {
     code: "代码",
     preview: "预览",
     cancel: "取消",
+    confirm: "确定",
     save: "保存",
     install: "安装",
     create: "创建",
@@ -80,6 +81,7 @@ export const zhCN: Translations = {
   // Input Box
   inputBox: {
     placeholder: "今天我能为你做些什么？",
+    editQuestion: "编辑问题",
     createSkillPrompt:
       "我们一起用 skill-creator 技能来创建一个技能吧。先问问我希望这个技能能做什么。",
     addAttachments: "添加附件",

frontend-web/src/core/settings/index.ts

@@ -1,3 +1,8 @@
 export { useLocalSettings, useThreadSettings } from "./hooks";
-export { isThreadRagModeLocked, lockThreadRagMode } from "./local";
+export {
+  getLastAgentId,
+  isThreadRagModeLocked,
+  lockThreadRagMode,
+  saveLastAgentId,
+} from "./local";
 export type { LocalSettings } from "./local";

frontend-web/src/core/settings/local.ts

@@ -21,6 +21,7 @@ export const DEFAULT_LOCAL_SETTINGS: LocalSettings = {
 export const LOCAL_SETTINGS_KEY = "deerflow.local-settings";
 export const THREAD_MODEL_KEY_PREFIX = "deerflow.thread-model.";
 export const THREAD_RAG_MODE_KEY_PREFIX = "deerflow.thread-rag-mode.";
+export const LAST_AGENT_ID_KEY = "deerflow.last-agent-id";
 
 function isBrowser(): boolean {
   return typeof window !== "undefined";
@@ -148,6 +149,29 @@ export function applyThreadModelOverride(
   };
 }
 
+/**
+ * The id of the agent the user last started a conversation with. New-chat
+ * landing screens pre-select this agent so the user doesn't have to re-pick it
+ * every time. Returns ``null`` when nothing was stored yet.
+ */
+export function getLastAgentId(): string | null {
+  if (!isBrowser()) {
+    return null;
+  }
+  return localStorage.getItem(LAST_AGENT_ID_KEY) || null;
+}
+
+export function saveLastAgentId(agentId: string | null | undefined) {
+  if (!isBrowser()) {
+    return;
+  }
+  if (!agentId) {
+    localStorage.removeItem(LAST_AGENT_ID_KEY);
+    return;
+  }
+  localStorage.setItem(LAST_AGENT_ID_KEY, agentId);
+}
+
 export function getLocalSettings(): LocalSettings {
   if (!isBrowser()) {
     return DEFAULT_LOCAL_SETTINGS;

frontend-web/src/core/skills/api.ts

@@ -202,6 +202,24 @@ export async function installSkillUpload(
   return response.json() as Promise<InstallSkillResponse>;
 }
 
+export async function duplicateSkill(
+  sourceName: string,
+  newName: string,
+): Promise<InstallSkillResponse> {
+  const response = await apiFetch(
+    `${getBackendBaseURL()}/api/skills/custom/${encodeURIComponent(sourceName)}/duplicate`,
+    {
+      method: "POST",
+      headers: { "Content-Type": "application/json" },
+      body: JSON.stringify({ new_name: newName }),
+    },
+  );
+  if (!response.ok) {
+    throw await parseDetailedError(response, "Failed to duplicate skill");
+  }
+  return response.json() as Promise<InstallSkillResponse>;
+}
+
 export interface ReconcileCustomSkillsResponse {
   adopted: string[];
   already_registered: string[];

frontend-web/src/core/skills/hooks.ts

@@ -7,6 +7,7 @@ import {
 
 import {
   deleteCustomSkill,
+  duplicateSkill,
   enableSkill,
   getSkill,
   getSkillContent,
@@ -192,6 +193,22 @@ export function useSetSkillPinned() {
   });
 }
 
+export function useDuplicateSkill() {
+  const queryClient = useQueryClient();
+  return useMutation({
+    mutationFn: ({
+      sourceName,
+      newName,
+    }: {
+      sourceName: string;
+      newName: string;
+    }) => duplicateSkill(sourceName, newName),
+    onSuccess: () => {
+      void queryClient.invalidateQueries({ queryKey: ["skills"] });
+    },
+  });
+}
+
 export function useDeleteCustomSkill() {
   const queryClient = useQueryClient();
   return useMutation({