feat: 品牌替换 + 启动优化 + AGENTS.md 模板定制

- 品牌替换：OpenCode/opencode → AirCoding/aircoding（16+ 文件）
- Logo ASCII art：修复 left/right 行数不匹配导致的启动崩溃
- 启动诊断：添加 OPENCODE_PRINT_TIMING 计时探针
- dev 模式默认 --pure 跳过外部插件加载
- AGENTS.md 模板：追加 AirCoding 多 Agent 专项段落
- architect prompt + plugin：强化 AGENTS.md 产出验证

packages/desktop/src/main/updater.ts

@@ -0,0 +1,68 @@
+import { app, dialog } from "electron"
+import pkg from "electron-updater"
+import { UPDATER_ENABLED } from "./constants"
+import { createUpdaterController, type UpdaterReadyRecord } from "./updater-controller"
+import { getLogger } from "./logging"
+import { getStore } from "./store"
+
+const { autoUpdater } = pkg
+const key = "ready"
+
+export function setupAutoUpdater(stop: () => Promise<void>) {
+  const logger = getLogger()
+  autoUpdater.logger = logger
+  autoUpdater.channel = "latest"
+  autoUpdater.allowPrerelease = false
+  autoUpdater.allowDowngrade = true
+  autoUpdater.autoDownload = false
+  autoUpdater.autoInstallOnAppQuit = false
+  logger.log("auto updater configured", {
+    channel: autoUpdater.channel,
+    allowPrerelease: autoUpdater.allowPrerelease,
+    allowDowngrade: autoUpdater.allowDowngrade,
+    currentVersion: app.getVersion(),
+  })
+
+  const store = getStore("opencode.updater")
+  return createUpdaterController({
+    enabled: UPDATER_ENABLED,
+    currentVersion: app.getVersion(),
+    backend: autoUpdater,
+    persistence: {
+      get() {
+        const value = store.get(key)
+        if (!value || typeof value !== "object" || !("version" in value) || typeof value.version !== "string") return
+        return { version: value.version } satisfies UpdaterReadyRecord
+      },
+      set: (value) => store.set(key, value),
+      clear: () => store.delete(key),
+    },
+    stop,
+    log: (message, data) => logger.log(message, data),
+  })
+}
+
+export async function showUpdaterDialog(controller: ReturnType<typeof setupAutoUpdater>, alertOnFail: boolean) {
+  const state = await controller.check()
+  if (state.status === "error") {
+    if (!alertOnFail) return
+    await dialog.showMessageBox({ type: "error", message: "Update check failed.", title: "Update Error" })
+    return
+  }
+  if (state.status === "up-to-date") {
+    if (!alertOnFail) return
+    await dialog.showMessageBox({ type: "info", message: "You're up to date.", title: "No Updates" })
+    return
+  }
+  if (state.status !== "ready") return
+
+  const response = await dialog.showMessageBox({
+    type: "info",
+    message: `Update ${state.version} downloaded. Restart now?`,
+    title: "Update Ready",
+    buttons: ["Restart", "Later"],
+    defaultId: 0,
+    cancelId: 1,
+  })
+  if (response.response === 0) await controller.install()
+}