feat: card repository and home three-column layout

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

@@ -2,6 +2,8 @@ package top.yeij.hearth.webview
 
 import android.util.Log
 import top.yeij.hearth.app.AppRepository
+import top.yeij.hearth.card.Card
+import top.yeij.hearth.card.CardRepository
 import top.yeij.hearth.webapp.WebApp
 import top.yeij.hearth.webapp.WebAppRepository
 
@@ -12,6 +14,7 @@ class JsBridge(
     private val darkMode: Boolean,
     private val appRepository: AppRepository? = null,
     private val webAppRepository: WebAppRepository? = null,
+    private val cardRepository: CardRepository? = null,
 ) {
     private val gson = com.google.gson.Gson()
 
@@ -42,4 +45,14 @@ class JsBridge(
     // Return the H5 web app manifest JSON (empty array when no repository wired)
     @android.webkit.JavascriptInterface
     fun fetchWebApps(): String = gson.toJson(webAppRepository?.fetchManifest() ?: emptyList<WebApp>())
+
+    // 返回首页卡片目录 JSON（无仓库时返回空数组；有仓库时由 fetchCatalog 保证内置 time 卡）
+    // Return the home card catalog JSON (empty array when no repository wired;
+    // fetchCatalog guarantees the builtin time card when wired)
+    @android.webkit.JavascriptInterface
+    fun fetchCards(): String {
+        val cards = cardRepository?.fetchCatalog() ?: emptyList<Card>()
+        Log.d("HearthBridge", "fetchCards: ${cards.size} cards")
+        return gson.toJson(cards)
+    }
 }