fix(desktop-runtime): 修复桌面端重装后仍命中旧 UI 缓存

- 启动打包版时按 UI buildId 检测并清理 renderer 缓存
- 记录 lastSeenUiBuildId，避免每次启动都重复清缓存
- 调整 SPA 静态资源缓存策略，index.html/200.html/_payload.json 禁止缓存
- 保留 _nuxt 哈希资源长期缓存，减少必须在卸载时删除数据后才生效的问题

desktop/src/main.cjs

@@ -7,6 +7,7 @@ const {
   globalShortcut,
   dialog,
   shell,
+  session,
 } = require("electron");
 let autoUpdater = null;
 let autoUpdaterLoadError = null;
@@ -465,6 +466,34 @@ function getDesktopSettingsPath() {
   return path.join(dir, "desktop-settings.json");
 }
 
+function getPackagedUiDir() {
+  if (!app.isPackaged) return null;
+  try {
+    return path.join(process.resourcesPath, "ui");
+  } catch {
+    return null;
+  }
+}
+
+function readPackagedUiBuildId() {
+  const uiDir = getPackagedUiDir();
+  if (!uiDir) return "";
+
+  try {
+    const indexPath = path.join(uiDir, "index.html");
+    if (!fs.existsSync(indexPath)) return "";
+    const html = fs.readFileSync(indexPath, { encoding: "utf8" });
+    const match =
+      html.match(/buildId:"([^"]+)"/) ||
+      html.match(/\/_payload\.json\?([^"'&<>\s]+)/) ||
+      html.match(/data-src="\/_payload\.json\?([^"]+)"/);
+    return String(match?.[1] || "").trim();
+  } catch (err) {
+    logMain(`[main] failed to read packaged UI build id: ${err?.message || err}`);
+    return "";
+  }
+}
+
 function loadDesktopSettings() {
   if (desktopSettings) return desktopSettings;
 
@@ -476,6 +505,9 @@ function loadDesktopSettings() {
     ignoredUpdateVersion: "",
     // Backend (FastAPI) listens on this port. Used in packaged builds.
     backendPort: DEFAULT_BACKEND_PORT,
+    // Tracks the packaged UI build so we can invalidate Chromium's HTTP cache
+    // after upgrades without wiping user data/localStorage.
+    lastSeenUiBuildId: "",
   };
 
   const p = getDesktopSettingsPath();
@@ -539,6 +571,33 @@ function setIgnoredUpdateVersion(version) {
   return desktopSettings.ignoredUpdateVersion;
 }
 
+async function refreshRendererCacheForPackagedUi() {
+  if (!app.isPackaged) return;
+
+  const nextBuildId = readPackagedUiBuildId();
+  if (!nextBuildId) return;
+
+  const prevBuildId = String(loadDesktopSettings()?.lastSeenUiBuildId || "").trim();
+  if (prevBuildId === nextBuildId) return;
+
+  try {
+    const ses = session?.defaultSession;
+    if (ses) {
+      await ses.clearCache();
+      try {
+        await ses.clearStorageData({ storages: ["serviceworkers"] });
+      } catch {}
+    }
+    logMain(`[main] cleared renderer cache for UI build change: ${prevBuildId || "(none)"} -> ${nextBuildId}`);
+  } catch (err) {
+    logMain(`[main] failed to clear renderer cache for UI build change: ${err?.message || err}`);
+  }
+
+  loadDesktopSettings();
+  desktopSettings.lastSeenUiBuildId = nextBuildId;
+  persistDesktopSettings();
+}
+
 function parseEnvBool(value) {
   if (value == null) return null;
   const v = String(value).trim().toLowerCase();
@@ -1614,6 +1673,7 @@ function registerWindowIpc() {
 
 async function main() {
   await app.whenReady();
+  await refreshRendererCacheForPackagedUi();
   Menu.setApplicationMenu(null);
   registerWindowIpc();
   registerDebugShortcuts();

src/wechat_decrypt_tool/api.py

@@ -99,9 +99,36 @@ class _SPAStaticFiles(StaticFiles):
         self._fallback_200 = Path(str(self.directory)) / "200.html"
         self._fallback_index = Path(str(self.directory)) / "index.html"
 
-    async def get_response(self, path: str, scope):  # type: ignore[override]
+    @staticmethod
+    def _normalize_path(path: str) -> str:
+        return str(path or "").strip().lstrip("/")
+
+    @classmethod
+    def _is_shell_path(cls, path: str) -> bool:
+        normalized = cls._normalize_path(path)
+        return normalized in {"", "index.html", "200.html", "_payload.json"} or normalized.startswith(
+            "_payload.json/"
+        )
+
+    @classmethod
+    def _apply_cache_headers(cls, path: str, response):
+        normalized = cls._normalize_path(path)
         try:
-            return await super().get_response(path, scope)
+            if cls._is_shell_path(normalized):
+                response.headers["Cache-Control"] = "no-store, no-cache, must-revalidate"
+                response.headers["Pragma"] = "no-cache"
+                response.headers["Expires"] = "0"
+            elif normalized.startswith("_nuxt/"):
+                response.headers.setdefault("Cache-Control", "public, max-age=31536000, immutable")
+        except Exception:
+            pass
+        return response
+
+    async def get_response(self, path: str, scope):  # type: ignore[override]
+        normalized = self._normalize_path(path)
+        try:
+            response = await super().get_response(path, scope)
+            return self._apply_cache_headers(normalized, response)
         except StarletteHTTPException as exc:
             if exc.status_code != 404:
                 raise
@@ -112,8 +139,8 @@ class _SPAStaticFiles(StaticFiles):
                 raise
 
             if self._fallback_200.exists():
-                return FileResponse(str(self._fallback_200))
-            return FileResponse(str(self._fallback_index))
+                return self._apply_cache_headers("200.html", FileResponse(str(self._fallback_200)))
+            return self._apply_cache_headers("index.html", FileResponse(str(self._fallback_index)))
 
 
 def _maybe_mount_frontend() -> None: