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/flared/runner.go

@@ -0,0 +1,85 @@
+package flared
+
+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/heartbeat"
+	"github.com/Rain-kl/Wavelet/internal/apps/flared/httpclient"
+	"github.com/Rain-kl/Wavelet/internal/apps/flared/sync"
+	"github.com/Rain-kl/Wavelet/internal/apps/flared/wsclient"
+)
+
+type Runner struct {
+	Config           *config.Config
+	HeartbeatService *heartbeat.Service
+	FrpcManager      *frpc.Manager
+	SyncService      *sync.Service
+	WebSocketService *wsclient.Client
+	HttpClient       *httpclient.Client
+}
+
+func (r *Runner) Run(ctx context.Context) error {
+	// Start background services
+	go r.HeartbeatService.Run(ctx)
+	go r.SyncService.Run(ctx)
+
+	// WebSocket reconnection loop
+	for {
+		select {
+		case <-ctx.Done():
+			r.FrpcManager.Stop()
+			return ctx.Err()
+		default:
+		}
+
+		conn, err := r.WebSocketService.Connect(ctx)
+		if err != nil {
+			slog.Error("flared ws connect failed, will retry", "error", err)
+			r.sleepContext(ctx, 5*time.Second)
+			continue
+		}
+
+		r.handleConnection(ctx, conn)
+		_ = conn.Close()
+		slog.Info("flared ws connection closed, reconnecting...")
+		r.sleepContext(ctx, 2*time.Second)
+	}
+}
+
+type flaredWSHandler struct {
+	runner *Runner
+}
+
+func (h *flaredWSHandler) OnConnect(ctx context.Context) error {
+	return nil
+}
+
+func (h *flaredWSHandler) HandleMessage(ctx context.Context, msg wsclient.WSMessage) error {
+	switch msg.Type {
+	case "active_config":
+		slog.Info("received config update notification from server")
+		h.runner.SyncService.Trigger()
+	default:
+		slog.Debug("ignored unknown ws message type", "type", msg.Type)
+	}
+	return nil
+}
+
+func (h *flaredWSHandler) OnClose(err error) {
+	slog.Error("flared ws receive failed", "error", err)
+}
+
+func (r *Runner) handleConnection(ctx context.Context, conn *wsclient.Connection) {
+	_ = conn.RunReceiveLoop(ctx, &flaredWSHandler{runner: r})
+}
+
+func (r *Runner) sleepContext(ctx context.Context, d time.Duration) {
+	select {
+	case <-ctx.Done():
+	case <-time.After(d):
+	}
+}