refactor(repo): replace legacy openflare-server with Wavelet rename

Delete the old monolithic openflare-server implementation and rename
Wavelet/ to openflare-server/ to complete the migration consolidation.
Update CI workflows, agent Dockerfiles, and deployment docs for the new
layout (frontend/, docker/Dockerfile).

openflare-server/internal/apps/admin/errs.go

@@ -0,0 +1,15 @@
+// Copyright 2025 linux.do
+// Copyright 2026 Arctel.net
+// SPDX-License-Identifier: Apache-2.0
+
+// Package admin 提供管理后台功能
+package admin
+
+// 管理后台错误消息常量
+const (
+	AdminRequired          = "未经授权访问"
+	TokenAdminRequired     = "该访问令牌没有管理员权限，无法访问管理端点" //nolint:gosec // false positive: this is an error message, not hardcoded credentials
+	InvalidAuthSourceID    = "认证源 ID 无效"
+	InvalidCursorParam     = "无效的 cursor 参数"
+	InvalidTaskExecutionID = "无效的任务执行记录 ID"
+)