增加智能体头像裁剪页面

- 新增 `AgentImageCropScreen.kt` 用于智能体头像的裁剪和预览。
- 调整导航逻辑，添加智能体时跳转到新的 `AgentImageCrop` 路由。
- 原有的 `ImageCropScreen` 专门用于处理个人资料头像的裁剪。
- `AddAgentViewModel` 中移除 `isFromAddAgent` 标志，通过不同的导航路由区分头像裁剪来源。

app/src/main/java/com/aiosman/ravenow/ui/Navi.kt

@@ -35,6 +35,7 @@ import com.aiosman.ravenow.ui.account.AccountSetting
 import com.aiosman.ravenow.ui.account.RemoveAccountScreen
 import com.aiosman.ravenow.ui.account.ResetPasswordScreen
 import com.aiosman.ravenow.ui.agent.AddAgentScreen
+import com.aiosman.ravenow.ui.agent.AgentImageCropScreen
 import com.aiosman.ravenow.ui.group.CreateGroupChatScreen
 import com.aiosman.ravenow.ui.chat.ChatAiScreen
 import com.aiosman.ravenow.ui.chat.ChatScreen
@@ -103,6 +104,7 @@ sealed class NavigationRoute(
     data object ChatGroup : NavigationRoute("ChatGroup/{id}/{name}/{avatar}")
     data object CommentNoticeScreen : NavigationRoute("CommentNoticeScreen")
     data object ImageCrop : NavigationRoute("ImageCrop")
+    data object AgentImageCrop : NavigationRoute("AgentImageCrop")
     data object AccountSetting : NavigationRoute("AccountSetting")
     data object AboutScreen : NavigationRoute("AboutScreen")
     data object AddAgent : NavigationRoute("AddAgent")
@@ -449,6 +451,13 @@ fun NavigationController(
                 ImageCropScreen()
             }
         }
+        composable(route = NavigationRoute.AgentImageCrop.route) {
+            CompositionLocalProvider(
+                LocalAnimatedContentScope provides this,
+            ) {
+                AgentImageCropScreen()
+            }
+        }
         composable(route = NavigationRoute.AccountSetting.route) {
             CompositionLocalProvider(
                 LocalAnimatedContentScope provides this,