feat: add Windows ARM64 support with x64-baseline CLI workaround (#2537)

* feat: add Windows ARM64 support with x64-baseline CLI workaround

Windows ARM64 native opencode.exe fails with a Bun FFI/TinyCC dlopen
error (anomalyco/opencode#19130). As a temporary workaround:

- Bundle x64-baseline OpenCode CLI on ARM64 instead of native ARM64
  (prepare-opencode-cli.mjs, env-runtime.js)
- Disable OpenCode self-upgrade on ARM64 in server, VS Code, and UI
  (upgrade-capability.js, opencode-upgrade-runtime.ts, useUIStore.ts,
  OpenCodeCliSettings.tsx, search.ts, SettingsView.tsx, platform.ts)
- Add ARM64 Windows cross-compile builds to release and smoke workflows
  (release.yml, release-desktop-smoke.yml)
- Refactor Windows latest.yml to use combine-electron-manifests pattern
  matching macOS, since two arches now produce per-arch manifests

The CI ARM64 build itself is permanent; only the x64-baseline CLI
bundling and upgrade disablement are temporary and should be reverted
when the upstream issue is resolved.

* fix(desktop): select Windows updater by architecture

---------

Co-authored-by: Bohdan Triapitsyn <artmore@protonmail.com>

packages/ui/src/stores/useUIStore.ts

@@ -10,6 +10,7 @@ import { getStoredMobileKeyboardMode, type MobileKeyboardMode } from '@/lib/mobi
 import { getRuntimeKey } from '@/lib/runtime-switch';
 import type { TerminalShell } from '@/lib/api/types';
 import { useFilesViewTabsStore } from './useFilesViewTabsStore';
+import { isWindowsArm64 } from '@/lib/platform';
 
 export type MainTab = 'chat' | 'plan' | 'git' | 'diff' | 'terminal' | 'files' | 'context' | 'diagram';
 export type PendingDiffScope = 'working' | 'staged' | 'turn';
@@ -999,7 +1000,7 @@ export const useUIStore = create<UIStore>()(
 
         showTerminalQuickKeysOnDesktop: false,
         persistChatDraft: true,
-        showOpenCodeUpdateNotifications: true,
+        showOpenCodeUpdateNotifications: !isWindowsArm64(),
         agentControlToolEnabled: true,
         inputSpellcheckEnabled: false,
         wideChatLayoutEnabled: false,