feat: add project profiles for snapshot-based config switching

Add a profile feature that captures the current provider, MCP,
skills and prompt state for Claude Code and Codex as a named
snapshot, and re-applies it in one click from the header switcher
or the tray Projects submenu.

- New profiles table (schema v12) with current marker in settings
- ProfileService orchestrates the four existing switch primitives
  (provider first, then MCP diff, skills diff, prompt enable)
- Best-effort apply: dangling references become warnings, no rollback
- Header combobox switcher + snapshot-style manage dialog
- Tray Projects submenu shared with the UI apply/event pipeline
- i18n for zh/en/ja/zh-TW under the new profiles domain
- Integration tests covering roundtrip, dangling refs and clear

src/lib/api/index.ts

@@ -3,6 +3,7 @@ export { providersApi, universalProvidersApi } from "./providers";
 export { settingsApi } from "./settings";
 export { backupsApi } from "./settings";
 export { mcpApi } from "./mcp";
+export { profilesApi } from "./profiles";
 export { promptsApi } from "./prompts";
 export { skillsApi } from "./skills";
 export { usageApi } from "./usage";
@@ -17,6 +18,7 @@ export * as authApi from "./auth";
 export * as copilotApi from "./copilot";
 export type { ProviderSwitchEvent } from "./providers";
 export type { Prompt } from "./prompts";
+export type { Profile, ProfilePayload, ProfilesResponse } from "./profiles";
 export type {
   CopilotDeviceCodeResponse,
   CopilotAuthStatus,

src/lib/api/profiles.ts

@@ -0,0 +1,83 @@
+import { invoke } from "@tauri-apps/api/core";
+
+/**
+ * 按 app 分槽的载荷容器（与后端 services/profile.rs 的 PerApp<T> 严格对应）
+ */
+export interface PerApp<T> {
+  claude: T;
+  codex: T;
+}
+
+/**
+ * 项目 Profile 的配置快照（与后端 ProfilePayload 严格对应）
+ */
+export interface ProfilePayload {
+  providers: PerApp<string | null>;
+  mcp: PerApp<string[]>;
+  skills: PerApp<string[]>;
+  prompts: PerApp<string | null>;
+}
+
+export interface Profile {
+  id: string;
+  name: string;
+  payload: ProfilePayload;
+  createdAt?: number;
+  updatedAt?: number;
+}
+
+export interface ProfilesResponse {
+  profiles: Profile[];
+  currentId: string | null;
+}
+
+export const profilesApi = {
+  /**
+   * 获取所有项目及当前激活项目 id
+   */
+  async list(): Promise<ProfilesResponse> {
+    return await invoke("list_profiles");
+  },
+
+  /**
+   * 以当前配置状态创建新项目
+   */
+  async create(name: string): Promise<Profile> {
+    return await invoke("create_profile", { name });
+  },
+
+  /**
+   * 更新项目（重命名和/或以当前状态重拍快照）
+   */
+  async update(
+    id: string,
+    options: { name?: string; resnapshot?: boolean },
+  ): Promise<Profile> {
+    return await invoke("update_profile", {
+      id,
+      name: options.name,
+      resnapshot: options.resnapshot,
+    });
+  },
+
+  /**
+   * 删除项目
+   */
+  async delete(id: string): Promise<void> {
+    return await invoke("delete_profile", { id });
+  },
+
+  /**
+   * 应用项目快照，返回 warnings（best-effort，部分失败不中断）
+   */
+  async apply(id: string): Promise<string[]> {
+    return await invoke("apply_profile", { id });
+  },
+
+  /**
+   * 不使用项目：仅清除激活标记，不改动任何配置
+   */
+  async clearCurrent(): Promise<void> {
+    return await invoke("clear_current_profile");
+  },
+};