refactor(repo): consolidate openflare-server to root and move subprojects to internal/apps

- Merge all files inside openflare-server to the repository root directory.
- Relocate agent, relay, and flared subprojects from internal/ to internal/apps/.
- Combine docker-compose files and update build context paths to root.
- Update GitHub workflows and Dockerfiles to refer to new directories and package names.
- Rewrite Go package imports across all files.
- Resolve database renew test race condition and clean up docs.

internal/apps/flared/sync/service.go

@@ -0,0 +1,88 @@
+package sync
+
+import (
+	"context"
+	"log/slog"
+	"time"
+
+	"github.com/Rain-kl/Wavelet/internal/apps/flared/config"
+	"github.com/Rain-kl/Wavelet/internal/apps/flared/frpc"
+	"github.com/Rain-kl/Wavelet/internal/apps/flared/httpclient"
+	service "github.com/Rain-kl/Wavelet/pkg/protocol"
+)
+
+type Service struct {
+	client      *httpclient.Client
+	frpcManager *frpc.Manager
+	config      *config.Config
+	triggerCh   chan struct{}
+}
+
+func New(client *httpclient.Client, manager *frpc.Manager, cfg *config.Config) *Service {
+	return &Service{
+		client:      client,
+		frpcManager: manager,
+		config:      cfg,
+		triggerCh:   make(chan struct{}, 1),
+	}
+}
+
+func (s *Service) Trigger() {
+	select {
+	case s.triggerCh <- struct{}{}:
+	default:
+	}
+}
+
+func (s *Service) Run(ctx context.Context) {
+	ticker := time.NewTicker(s.config.SyncInterval.Duration())
+	defer ticker.Stop()
+
+	// initial sync
+	s.doSync(ctx)
+
+	for {
+		select {
+		case <-ctx.Done():
+			return
+		case <-ticker.C:
+			s.doSync(ctx)
+		case <-s.triggerCh:
+			s.doSync(ctx)
+		}
+	}
+}
+
+func (s *Service) doSync(ctx context.Context) {
+	slog.Debug("fetching active tunnel config")
+	configResp, err := s.client.GetActiveConfig(ctx)
+	if err != nil {
+		slog.Error("failed to fetch active tunnel config", "error", err)
+		return
+	}
+
+	// 不在 sync 层做版本早退，由 frpcManager.UpdateConfig 负责判断。
+	// 原因：重启后进程全部消失，即使版本/checksum 未变，仍需重新拉起 frpc 进程。
+	err = s.frpcManager.UpdateConfig(ctx, configResp)
+
+	result := "success"
+	message := "apply success"
+	if err != nil {
+		result = "failed"
+		message = err.Error()
+		slog.Error("failed to apply tunnel config", "error", err)
+	} else {
+		slog.Info("tunnel config applied successfully", "version", configResp.Version)
+	}
+
+	// Report apply log
+	logPayload := service.ApplyLogPayload{
+		Version:  configResp.Version,
+		Result:   result,
+		Message:  message,
+		Checksum: configResp.Checksum,
+	}
+	if reportErr := s.client.ReportApplyLog(ctx, logPayload); reportErr != nil {
+		slog.Error("failed to report apply log", "error", reportErr)
+	}
+}