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/db/errs.go

@@ -0,0 +1,12 @@
+// Copyright 2026 Arctel.net
+// SPDX-License-Identifier: Apache-2.0
+
+package db
+
+const (
+	errRedisHashSetFailed    = "failed to set redis hash: %w"
+	errRedisHashDeleteFailed = "failed to delete redis hash field: %w"
+	errUnmarshalDataFailed   = "failed to unmarshal data: %w"
+	errMarshalDataFailed     = "failed to marshal data: %w"
+	errRedisKeySetFailed     = "failed to set redis key: %w"
+)