refactor(auth): unify Facebook and Google login into AuthPlatform class

Replace the separate FacebookLogin and GoogleLogin classes with a single
AuthPlatform class that takes a provider name ("facebook" | "google") as a
constructor argument. This consolidates duplicate OAuth sign-in logic behind
one entry point while preserving the existing NextAuth flow.

- Add new src/lib/auth/auth_platform.ts exporting AuthPlatform and
  AuthProvider type
- Update auth-facebook-panel.tsx and splash-button.tsx to use the new API
- Rename initialContext → initialState in the auth machine for consistency
- Update inline docs and comments to reference AuthPlatform

No behavioral change for end users; both providers still route through
NextAuth's signIn() with the same callbacks and cookies.

src/stores/auth/auth-state.ts

@@ -1,11 +1,11 @@
 /**
- * Auth 状态机：Context 形状 + 初始值
+ * Auth 状态机：State 形状 + 初始值
  */
 import type { AuthMode } from "@/models/auth/auth-mode";
 import type { AuthPanelMode } from "@/models/auth/auth-panel-mode";
 import type { LoginType } from "@/models/auth/login-type";
 
-export interface AuthContext {
+export interface AuthState {
   /** 当前面板模式（Facebook / Email） */
   authPanelMode: AuthPanelMode;
   /** 内部登录模式（login / register） */
@@ -18,7 +18,7 @@ export interface AuthContext {
   loginType: LoginType;
 }
 
-export const initialContext: AuthContext = {
+export const initialState: AuthState = {
   authPanelMode: "facebook",
   authMode: "login",
   email: "",

src/stores/auth/auth-types.ts

@@ -7,4 +7,4 @@
  *   - Context 形状与初始值由 `auth-context.ts` 导出
  *   - `AuthState` 由 `auth-context.tsx` 导出（保持原 API 兼容）
  */
-export type { AuthEvent } from "./auth-events";
+export type { AuthEvent } from "./machine/auth-events";

src/stores/auth/index.ts

@@ -6,7 +6,8 @@
  *   - 事件联合位于 auth-events.ts
  *   - machine / 类型 / React 入口分别由对应文件导出
  */
+export * from "./auth-state";
 export * from "./auth-context";
-export * from "./auth-events";
-export * from "./auth-machine";
+export * from "./machine/auth-events";
+export * from "./machine/auth-machine";
 export * from "./auth-types";

src/stores/auth/machine/auth-context.tsx

@@ -18,12 +18,12 @@ import {
 import { useMachine } from "@xstate/react";
 
 import { authMachine } from "./auth-machine";
-import type { AuthEvent, AuthContext as MachineContext } from "./auth-machine";
+import type { AuthEvent, AuthState as MachineContext } from "./auth-machine";
 
 /**
  * 对外暴露的 State 形状（保持与原 AuthState 兼容）
  */
-export interface AuthState {
+interface AuthState {
   authPanelMode: MachineContext["authPanelMode"];
   authMode: MachineContext["authMode"];
   email: string;

src/stores/auth/machine/auth-machine.ts

@@ -4,8 +4,8 @@
  * 原始 Dart: lib/ui/auth/bloc/auth_bloc.dart + auth_state.dart + auth_event.dart
  *
  * 本轮迁移：社交登录改由 NextAuth 处理（`@/lib/auth/nextauth`），状态机仅保留
- * 邮箱注册/登录 + 通用 reset 事件。社交登录走 `new GoogleLogin().signIn()` /
- * `new FacebookLogin().signIn()`。
+ * 邮箱注册/登录 + 通用 reset 事件。社交登录走 `new AuthPlatform("google").signIn()` /
+ * `new AuthPlatform("facebook").signIn()`。
  */
 import { setup, fromPromise, assign } from "xstate";
 
@@ -14,12 +14,12 @@ import { authRepository } from "@/data/repositories/auth_repository";
 import { AuthStorage } from "@/data/storage/auth/auth_storage";
 import { Result } from "@/utils/result";
 
-import { AuthContext, initialContext } from "./auth-context";
+import { AuthState, initialState } from "../auth-state";
 import type { AuthEvent } from "./auth-events";
 
-// 重新导出 Context / Event 类型，保持 machine 文件的公共 API 不变
-export type { AuthContext } from "./auth-context";
-export { initialContext } from "./auth-context";
+// 重新导出 State / Event 类型，保持 machine 文件的公共 API 不变
+export type { AuthState } from "../auth-state";
+export { initialState } from "../auth-state";
 export type { AuthEvent } from "./auth-events";
 
 // ============================================================
@@ -73,7 +73,7 @@ const emailRegisterThenLoginActor = fromPromise<
 // ============================================================
 export const authMachine = setup({
   types: {
-    context: {} as AuthContext,
+    context: {} as AuthState,
     events: {} as AuthEvent,
   },
   actors: {
@@ -83,7 +83,7 @@ export const authMachine = setup({
 }).createMachine({
   id: "auth",
   initial: "idle",
-  context: initialContext,
+  context: initialState,
   states: {
     idle: {
       on: {
@@ -109,11 +109,11 @@ export const authMachine = setup({
           }),
         },
         AuthReset: {
-          actions: assign(() => initialContext),
+          actions: assign(() => initialState),
         },
         AuthEmailLoginSubmitted: "loadingEmailLogin",
         AuthEmailRegisterSubmitted: "loadingEmailRegister",
-        // 社交登录已迁移到 NextAuth + GoogleLogin / FacebookLogin 类
+        // 社交登录已迁移到 NextAuth + AuthPlatform 类
         // 状态机保留事件以兼容旧调用方（实际不再触发）
         AuthGoogleLoginSubmitted: {},
         AuthFacebookLoginSubmitted: {},

src/stores/chat/chat-context.tsx

@@ -20,13 +20,13 @@ import {
 } from "react";
 import { useMachine } from "@xstate/react";
 
-import { chatMachine } from "./chat-machine";
-import type { ChatEvent, ChatContext as MachineContext } from "./chat-machine";
+import { chatMachine } from "./machine/chat-machine";
+import type { ChatEvent, ChatState as MachineContext } from "./machine/chat-machine";
 
 /**
  * 对外暴露的 State 形状（保持与原 ChatState 兼容）
  */
-export interface ChatState {
+interface ChatState {
   messages: MachineContext["messages"];
   isReplyingAI: boolean;
   isGuest: boolean;

src/stores/chat/chat-types.ts

@@ -8,5 +8,5 @@
  *   - `ChatState` 由 `chat-context.tsx` 导出（保持原 API 兼容）
  *   - `GuestChatQuota` 仍由 `chat-machine.ts` 导出（业务常量，与上下文配对紧密）
  */
-export type { ChatEvent } from "./chat-events";
+export type { ChatEvent } from "./machine/chat-events";
 export { GuestChatQuota } from "./chat-machine";

src/stores/chat/index.ts

@@ -11,7 +11,8 @@
  * 注：chat-side-effects.ts 暂未删除（其中 WebSocket 长生命周期逻辑
  * 待下一轮迁移到 fromCallback actor）。
  */
+export * from "./machine/chat-state";
 export * from "./chat-context";
-export * from "./chat-events";
+export * from "./machine/chat-events";
 export * from "./chat-types";
 export { chatMachine } from "./chat-machine";

src/stores/chat/machine/chat-machine.ts

@@ -23,8 +23,8 @@ import { AuthStorage } from "@/data/storage/auth/auth_storage";
 import { formatDate } from "@/utils/date";
 import { Result } from "@/utils/result";
 
-import { ChatContext, initialContext } from "./chat-context";
-import type { ChatEvent } from "./chat-events";
+import { ChatState, initialState } from "./chat-state";
+import type { ChatEvent } from "./machine/chat-events";
 
 /** 游客配额阈值（与 Dart `GuestChatQuota` 保持一致） */
 export const GuestChatQuota = {
@@ -32,10 +32,10 @@ export const GuestChatQuota = {
   quotaExhausted: 0,
 } as const;
 
-// 重新导出 Context / Event 类型，保持 machine 文件的公共 API 不变
-export type { ChatContext } from "./chat-context";
-export { initialContext } from "./chat-context";
-export type { ChatEvent } from "./chat-events";
+// 重新导出 State / Event 类型，保持 machine 文件的公共 API 不变
+export type { ChatState } from "./chat-state";
+export { initialState } from "./chat-state";
+export type { ChatEvent } from "./machine/chat-events";
 
 // ============================================================
 // Helpers
@@ -146,7 +146,7 @@ const loadMoreHistoryActor = fromPromise<
 // ============================================================
 export const chatMachine = setup({
   types: {
-    context: {} as ChatContext,
+    context: {} as ChatState,
     events: {} as ChatEvent,
   },
   actors: {
@@ -230,7 +230,7 @@ export const chatMachine = setup({
 }).createMachine({
   id: "chat",
   initial: "idle",
-  context: initialContext,
+  context: initialState,
   states: {
     idle: {
       on: {

src/stores/chat/machine/chat-state.ts

@@ -1,11 +1,11 @@
 /**
- * Chat 状态机：Context 形状 + 初始值
+ * Chat 状态机：State 形状 + 初始值
  *
  * 注：GuestChatQuota 仍位于 chat-machine.ts（属于业务常量，与上下文配对紧密）。
  */
 import type { UiMessage } from "@/models/chat/ui-message";
 
-export interface ChatContext {
+export interface ChatState {
   messages: UiMessage[];
   isReplyingAI: boolean;
   isGuest: boolean;
@@ -17,7 +17,7 @@ export interface ChatContext {
   historyOffset: number;
 }
 
-export const initialContext: ChatContext = {
+export const initialState: ChatState = {
   messages: [],
   isReplyingAI: false,
   isGuest: true,

src/stores/sidebar/index.ts

@@ -8,7 +8,8 @@
  *   - Context 形状与初始值位于 sidebar-context.ts
  *   - 事件联合位于 sidebar-events.ts
  */
+export * from "./sidebar-state";
 export * from "./sidebar-context";
 export * from "./sidebar-events";
 export * from "./sidebar-types";
-export { sidebarMachine } from "./sidebar-machine";
+export { sidebarMachine } from "./machine/sidebar-machine";

src/stores/sidebar/machine/sidebar-machine.ts

@@ -11,7 +11,7 @@
  */
 import { setup, assign } from "xstate";
 
-import { SidebarContext, initialContext } from "./sidebar-context";
+import { SidebarState, initialState } from "../sidebar-state";
 import type { SidebarEvent } from "./sidebar-events";
 
 /**
@@ -36,9 +36,9 @@ export const BottomNavItem = {
 
 export type BottomNavItem = (typeof BottomNavItem)[keyof typeof BottomNavItem];
 
-// 重新导出 Context / Event 类型，保持 machine 文件的公共 API 不变
-export type { SidebarContext } from "./sidebar-context";
-export { initialContext } from "./sidebar-context";
+// 重新导出 State / Event 类型，保持 machine 文件的公共 API 不变
+export type { SidebarState } from "../sidebar-state";
+export { initialState } from "../sidebar-state";
 export type { SidebarEvent } from "./sidebar-events";
 
 // ============================================================
@@ -46,7 +46,7 @@ export type { SidebarEvent } from "./sidebar-events";
 // ============================================================
 export const sidebarMachine = setup({
   types: {
-    context: {} as SidebarContext,
+    context: {} as SidebarState,
     events: {} as SidebarEvent,
   },
   actions: {
@@ -73,7 +73,7 @@ export const sidebarMachine = setup({
 }).createMachine({
   id: "sidebar",
   initial: "idle",
-  context: initialContext,
+  context: initialState,
   states: {
     /**
      * Sidebar 是纯数据状态（无异步副作用），仅用 idle 状态

src/stores/sidebar/machine/sidebar-state.ts

@@ -1,18 +1,18 @@
 /**
- * Sidebar 状态机：Context 形状 + 初始值
+ * Sidebar 状态机：State 形状 + 初始值
  *
  * SidebarPage / BottomNavItem 仍由 sidebar-machine.ts 导出（事件/上下文均需引用）。
  */
-import { SidebarPage, BottomNavItem } from "./sidebar-machine";
+import { SidebarPage, BottomNavItem } from "./machine/sidebar-machine";
 
-export interface SidebarContext {
+export interface SidebarState {
   currentPage: SidebarPage;
   selectedBottomNavItem: BottomNavItem;
   characterName: string;
   characterProgress: number;
 }
 
-export const initialContext: SidebarContext = {
+export const initialState: SidebarState = {
   currentPage: SidebarPage.DefaultView,
   selectedBottomNavItem: BottomNavItem.None,
   characterName: "Luna",

src/stores/sidebar/sidebar-context.tsx

@@ -17,16 +17,16 @@ import {
 } from "react";
 import { useMachine } from "@xstate/react";
 
-import { sidebarMachine } from "./sidebar-machine";
+import { sidebarMachine } from "./machine/sidebar-machine";
 import type {
-  SidebarContext as MachineContext,
+  SidebarState as MachineContext,
   SidebarEvent,
-} from "./sidebar-machine";
+} from "./machine/sidebar-machine";
 
 /**
  * 对外暴露的 State 形状（保持与原 SidebarState 兼容）
  */
-export interface SidebarState {
+interface SidebarState {
   currentPage: MachineContext["currentPage"];
   selectedBottomNavItem: MachineContext["selectedBottomNavItem"];
   characterName: string;

src/stores/sidebar/sidebar-types.ts

@@ -8,5 +8,5 @@
  *   - Context 形状由 `sidebar-context.ts` 导出
  *   - SidebarState 由 `sidebar-context.tsx` 导出（保持原 API 兼容）
  */
-export { SidebarPage, BottomNavItem } from "./sidebar-machine";
+export { SidebarPage, BottomNavItem } from "./machine/sidebar-machine";
 export type { SidebarEvent } from "./sidebar-events";

src/stores/user/index.ts

@@ -8,7 +8,8 @@
  *   - Context 形状与初始值位于 user-context.ts
  *   - 事件联合位于 user-events.ts
  */
+export * from "./machine/user-state";
 export * from "./user-context";
-export * from "./user-events";
+export * from "./machine/user-events";
 export * from "./user-types";
 export { userMachine } from "./user-machine";

src/stores/user/machine/user-machine.ts

@@ -17,13 +17,13 @@ import { authRepository } from "@/data/repositories/auth_repository";
 import { UserStorage } from "@/data/storage/user/user_storage";
 import { Result } from "@/utils/result";
 
-import { UserContext, initialContext } from "./user-context";
-import type { UserEvent } from "./user-events";
+import { UserState, initialState } from "./machine/user-state";
+import type { UserEvent } from "./machine/user-events";
 
-// 重新导出 Context / Event 类型，保持 machine 文件的公共 API 不变
-export type { UserContext } from "./user-context";
-export { initialContext } from "./user-context";
-export type { UserEvent } from "./user-events";
+// 重新导出 State / Event 类型，保持 machine 文件的公共 API 不变
+export type { UserState } from "./machine/user-state";
+export { initialState } from "./machine/user-state";
+export type { UserEvent } from "./machine/user-events";
 
 // ============================================================
 // Helpers
@@ -102,7 +102,7 @@ const userLogoutActor = fromPromise<void>(async () => {
 // ============================================================
 export const userMachine = setup({
   types: {
-    context: {} as UserContext,
+    context: {} as UserState,
     events: {} as UserEvent,
   },
   actors: {
@@ -136,7 +136,7 @@ export const userMachine = setup({
 }).createMachine({
   id: "user",
   initial: "idle",
-  context: initialContext,
+  context: initialState,
   states: {
     idle: {
       on: {

src/stores/user/machine/user-state.ts

@@ -1,9 +1,9 @@
 /**
- * User 状态机：Context 形状 + 初始值
+ * User 状态机：State 形状 + 初始值
  */
 import type { UserView } from "@/models/user/user";
 
-export interface UserContext {
+export interface UserState {
   currentUser: UserView | null;
   pronouns: string;
   coinBalance: number;
@@ -11,7 +11,7 @@ export interface UserContext {
   avatarUrl: string | null;
 }
 
-export const initialContext: UserContext = {
+export const initialState: UserState = {
   currentUser: null,
   pronouns: "He",
   coinBalance: 45,

src/stores/user/user-context.tsx

@@ -18,12 +18,12 @@ import {
 import { useMachine } from "@xstate/react";
 
 import { userMachine } from "./user-machine";
-import type { UserContext as MachineContext, UserEvent } from "./user-machine";
+import type { UserState as MachineContext, UserEvent } from "./user-machine";
 
 /**
  * 对外暴露的 State 形状（保持与原 UserState 兼容）
  */
-export interface UserState {
+interface UserState {
   currentUser: MachineContext["currentUser"];
   pronouns: string;
   coinBalance: number;

src/stores/user/user-types.ts

@@ -7,4 +7,4 @@
  *   - Context 形状与初始值由 `user-context.ts` 导出
  *   - `UserState` 由 `user-context.tsx` 导出（保持原 API 兼容）
  */
-export type { UserEvent } from "./user-events";
+export type { UserEvent } from "./machine/user-events";