refactor: modularize launcher UI and native services with verified IO

src/services/native.ts

@@ -0,0 +1,47 @@
+import { invoke, isTauri } from '@tauri-apps/api/core'
+import { listen } from '@tauri-apps/api/event'
+import { createSubscription, singleFlight } from './async'
+import type {
+  DeviceCodePayload, GameExitedPayload, InstallProgressPayload,
+  JavaInstallation, LauncherSettings, LoginResultPayload, MinecraftProfile,
+  NativeHost, ProfileInspection, SyncResult,
+} from '../types/launcher'
+
+export const isNative = () => typeof window !== 'undefined' && isTauri()
+const restoreAccount = singleFlight(() => invoke<MinecraftProfile | null>('get_account'))
+
+// Keep the IPC contract in one place. UI components never invoke native
+// commands directly and cannot pass arbitrary URLs or filesystem paths.
+export const native = {
+  host: () => invoke<NativeHost>('native_host'),
+  loadSettings: () => invoke<LauncherSettings>('load_settings'),
+  saveSettings: (settings: LauncherSettings) => invoke<LauncherSettings>('save_settings', { settings }),
+  detectJava: () => invoke<JavaInstallation | null>('detect_java'),
+  inspectProfile: (profileId: string) => invoke<ProfileInspection>('inspect_remote_profile', { profileId }),
+  syncProfile: (profileId: string) => invoke<SyncResult>('sync_remote_profile', { profileId }),
+  getAccount: restoreAccount,
+  startLogin: () => invoke<void>('start_microsoft_login'),
+  logout: () => invoke<void>('logout'),
+  installGame: (profileId: string) => invoke<void>('ensure_game_installed', { profileId }),
+  launchGame: (profileId: string) => invoke<void>('launch_game', { profileId }),
+}
+
+export function watchAccount(handlers: {
+  code: (payload: DeviceCodePayload) => void
+  result: (payload: LoginResultPayload) => void
+}) {
+  return createSubscription([
+    listen<DeviceCodePayload>('msa-login-code', ({ payload }) => handlers.code(payload)),
+    listen<LoginResultPayload>('msa-login-result', ({ payload }) => handlers.result(payload)),
+  ])
+}
+
+export function watchGame(handlers: {
+  progress: (payload: InstallProgressPayload) => void
+  exited: (payload: GameExitedPayload) => void
+}) {
+  return createSubscription([
+    listen<InstallProgressPayload>('game-install-progress', ({ payload }) => handlers.progress(payload)),
+    listen<GameExitedPayload>('game-exited', ({ payload }) => handlers.exited(payload)),
+  ])
+}