feat: check-update diff report and list refresh

app/src/main/java/top/yeij/hearth/webview/JsBridge.kt

@@ -419,16 +419,38 @@ class JsBridge(
     @android.webkit.JavascriptInterface
     fun getWallpaper(): String = wallpaper?.getWallpaperBase64() ?: ""
 
-    // 重新拉取 webAPP 清单 + 卡片目录，返回 { count }
-    // Re-fetch the webAPP manifest + card catalog, return { count }
+    // 重新拉取 webAPP 清单 + 卡片目录，返回 { added, removed, changed }
+    // Re-fetch the webAPP manifest + card catalog, return { added, removed, changed }
     @android.webkit.JavascriptInterface
     fun refreshManifest(): String {
+        val oldApps = manifestCache ?: emptyList<WebApp>()
         manifestCache = null
         val apps = webAppRepository?.fetchManifest() ?: emptyList<WebApp>()
         if (apps.isNotEmpty()) manifestCache = apps
-        val cards = cardRepository?.fetchCatalog() ?: emptyList<Card>()
-        Log.d("HearthBridge", "refreshManifest: ${apps.size} apps, ${cards.size} cards")
-        return gson.toJson(mapOf("count" to apps.size))
+        cardRepository?.fetchCatalog()
+
+        // 增量计算：新增 / 移除 / 更新（离线包版本或 URL/图标变化）
+        // Diff: added / removed / changed (offline version or URL/icon changed)
+        val oldIds = oldApps.map { it.id }.toSet()
+        val newIds = apps.map { it.id }.toSet()
+        val added = (newIds - oldIds).size
+        val removed = (oldIds - newIds).size
+        val changed = apps.count { new ->
+            val old = oldApps.find { it.id == new.id }
+            old != null && (old.offlineVersion != new.offlineVersion ||
+                old.url != new.url || old.icon != new.icon)
+        }
+        Log.d("HearthBridge", "refreshManifest: added=$added removed=$removed changed=$changed (${apps.size} apps)")
+
+        // 推送 H5 刷新列表（清 preload 缓存并重渲染）
+        // Push H5 to refresh the list (clear preload cache and re-render)
+        desktopWebViewRef?.post {
+            desktopWebViewRef?.evaluateJavascript(
+                "window.HearthEvents && window.HearthEvents.webappUpdated();",
+                null
+            )
+        }
+        return gson.toJson(mapOf("added" to added, "removed" to removed, "changed" to changed))
     }
 
     // 注册媒体会话监听，回调推送给 H5（info 为 null 时推 "null"）