Reset ViewModels on logout/account switch

This commit introduces a `ResetModel()` function to `AgentViewModel` and `MineAgentViewModel` to clear their state.

This function is now called in `ResourceCleanupManager` and `AppState` during logout or when switching accounts to ensure that data from the previous session is not retained.

Additionally, the search and group name input fields in `CreateGroupChatScreen` are now single-line.

app/src/main/java/com/aiosman/ravenow/ui/index/tabs/ai/AgentViewModel.kt

@@ -95,4 +95,14 @@ object AgentViewModel: ViewModel() {
         }
     }
 
+    /**
+     * 重置ViewModel状态，用于登出或切换账号时清理数据
+     */
+    fun ResetModel() {
+        agentItems = emptyList()
+        errorMessage = null
+        isRefreshing = false
+        isLoading = false
+    }
+
 }

app/src/main/java/com/aiosman/ravenow/ui/index/tabs/ai/tabs/mine/MineAgentViewModel.kt

@@ -139,5 +139,23 @@ object MineAgentViewModel : ViewModel() {
         }
     }
     
+    /**
+     * 重置ViewModel状态，用于登出或切换账号时清理数据
+     */
+    fun ResetModel() {
+        // 重置状态变量
+        refreshing = false
+        isLoading = false
+        hasNext = true
+        currentPage = 1
+        error = null
+        isFirstLoad = true
+        
+        // 清除预加载的图片ID
+        preloadedImageIds.clear()
+        
+        // 清空PagingData
+        _agentList.value = PagingData.empty()
+    }
 
 }