refactor: migrate state imports from contexts to stores directory

src/stores/user/user-context.tsx

@@ -0,0 +1,78 @@
+"use client";
+/**
+ * UserContext：基于 XState v5 的 React Context Provider
+ *
+ * 业务事件通过 `useMachine(userMachine).send()` 派发。
+ * XState 自动处理异步副作用（invoke + fromPromise actors）。
+ *
+ * 兼容性：保持原 `useUserState()` / `useUserDispatch()` API。
+ * 内部将 XState 状态机快照映射回原 `UserState` 形状。
+ */
+import {
+  type Dispatch,
+  type ReactNode,
+  createContext,
+  useContext,
+  useMemo,
+} from "react";
+import { useMachine } from "@xstate/react";
+
+import { userMachine } from "./user-machine";
+import type { UserContext as MachineContext, UserEvent } from "./user-machine";
+
+/**
+ * 对外暴露的 State 形状（保持与原 UserState 兼容）
+ */
+export interface UserState {
+  currentUser: MachineContext["currentUser"];
+  pronouns: string;
+  coinBalance: number;
+  isLoading: boolean;
+  avatarUrl: string | null;
+}
+
+const UserStateCtx = createContext<UserState | null>(null);
+const UserDispatchCtx = createContext<Dispatch<UserEvent> | null>(null);
+
+export interface UserProviderProps {
+  children: ReactNode;
+}
+
+export function UserProvider({ children }: UserProviderProps) {
+  const [state, send] = useMachine(userMachine);
+
+  // 映射 XState 状态机快照 → 原 UserState 形状
+  const userState = useMemo<UserState>(
+    () => ({
+      currentUser: state.context.currentUser,
+      pronouns: state.context.pronouns,
+      coinBalance: state.context.coinBalance,
+      isLoading:
+        state.matches("initializing") ||
+        state.matches("fetching") ||
+        state.matches("loggingOut") ||
+        state.context.isLoading,
+      avatarUrl: state.context.avatarUrl,
+    }),
+    [state],
+  );
+
+  return (
+    <UserStateCtx.Provider value={userState}>
+      <UserDispatchCtx.Provider value={send}>{children}</UserDispatchCtx.Provider>
+    </UserStateCtx.Provider>
+  );
+}
+
+export function useUserState(): UserState {
+  const ctx = useContext(UserStateCtx);
+  if (!ctx) throw new Error("useUserState must be used inside <UserProvider>");
+  return ctx;
+}
+
+export function useUserDispatch(): Dispatch<UserEvent> {
+  const ctx = useContext(UserDispatchCtx);
+  if (!ctx)
+    throw new Error("useUserDispatch must be used inside <UserProvider>");
+  return ctx;
+}