修复一些未处理异常，切换到测试服务器

app/src/main/java/com/aiosman/ravenow/entity/Agent.kt

@@ -80,9 +80,9 @@ class AgentPagingSource(
                 authorId = authorId
             )
             LoadResult.Page(
-                data = users.list,
+                data = users?.list ?: listOf(),
                 prevKey = if (currentPage == 1) null else currentPage - 1,
-                nextKey = if (users.list.isEmpty()) null else users.page + 1
+                nextKey = if (users?.list?.isNotEmpty() == true) users.page + 1 else  null
             )
         } catch (exception: IOException) {
             return LoadResult.Error(exception)
@@ -102,7 +102,7 @@ class AgentRemoteDataSource(
     suspend fun getAgent(
         pageNumber: Int,
         authorId: Int? = null
-    ): ListContainer<AgentEntity> {
+    ): ListContainer<AgentEntity>? {
         return agentService.getAgent(
             pageNumber = pageNumber,
             authorId = authorId
@@ -117,7 +117,7 @@ class AgentServiceImpl() : AgentService {
         pageNumber: Int,
         pageSize: Int,
         authorId: Int?
-    ): ListContainer<AgentEntity> {
+    ): ListContainer<AgentEntity>? {
         return agentBackend.getAgent(
             pageNumber = pageNumber,
             authorId = authorId
@@ -130,7 +130,7 @@ class AgentBackend {
     suspend fun getAgent(
         pageNumber: Int,
         authorId: Int? = null
-    ): ListContainer<AgentEntity> {
+    ): ListContainer<AgentEntity>? {
         // 如果是游客模式且获取我的Agent（authorId为null），返回空列表
         if (authorId == null && AppStore.isGuest) {
             return ListContainer(
@@ -154,7 +154,7 @@ class AgentBackend {
             )
         }
 
-        val body = resp.body() ?: throw ServiceException("Failed to get agents")
+        val body = resp.body() ?: return null
 
         // 处理不同的返回类型
         return if (authorId != null) {