refactor(edge): 抽取边缘运行时共享包并完成 Phase 3 重构

- 新增 internal/apps/edge/，三组件改为薄包装，删除 3000+ 行重复代码
- Agent 心跳周期下沉至 heartbeat/cycle.go
- 协议类型迁入 pkg/protocol/agent.go
- 补充设计文档与 changelog

cmd/agent/main.go

@@ -92,15 +92,23 @@ func main() {
 	}
 	syncService := syncservice.New(client, runtimeManager, stateStore)
 	syncService.SetPagesDir(cfg.PagesDir)
+	heartbeatService := heartbeat.New(client)
+	updateService := updater.New()
 	runner := &agent.Runner{
-		Config:              cfg,
-		StateStore:          stateStore,
-		ObservabilityBuffer: observabilityBuffer,
-		HeartbeatService:    heartbeat.New(client),
-		SyncService:         syncService,
-		Updater:             updater.New(),
-		RuntimeManager:      runtimeManager,
-		WebSocketService:    wsClient,
+		Config:           cfg,
+		StateStore:       stateStore,
+		HeartbeatCycle: &heartbeat.Cycle{
+			Config:              cfg,
+			StateStore:          stateStore,
+			ObservabilityBuffer: observabilityBuffer,
+			Heartbeat:           heartbeatService,
+			Sync:                syncService,
+			Updater:             updateService,
+		},
+		HeartbeatService: heartbeatService,
+		SyncService:      syncService,
+		RuntimeManager:   runtimeManager,
+		WebSocketService: wsClient,
 	}
 
 	ctx, stop := signal.NotifyContext(context.Background(), syscall.SIGINT, syscall.SIGTERM)

cmd/flared/main.go

@@ -6,9 +6,9 @@ import (
 	"log/slog"
 	"os"
 	"os/signal"
-	"strings"
 	"syscall"
 
+	edgelogging "github.com/Rain-kl/Wavelet/internal/apps/edge/logging"
 	"github.com/Rain-kl/Wavelet/internal/apps/flared/config"
 	"github.com/Rain-kl/Wavelet/internal/apps/flared/flared"
 	"github.com/Rain-kl/Wavelet/internal/apps/flared/frpc"
@@ -19,10 +19,7 @@ import (
 )
 
 func main() {
-	// Setup simple structured logging
-	slog.SetDefault(slog.New(slog.NewTextHandler(os.Stdout, &slog.HandlerOptions{
-		Level: parseLevel(os.Getenv("LOG_LEVEL")),
-	})))
+	edgelogging.Setup(edgelogging.Options{})
 
 	configPath := flag.String("config", "./flared.json", "flared config path")
 	flag.Parse()
@@ -72,16 +69,3 @@ func main() {
 	}
 	slog.Info("flared process stopped")
 }
-
-func parseLevel(value string) slog.Level {
-	switch strings.ToLower(strings.TrimSpace(value)) {
-	case "debug":
-		return slog.LevelDebug
-	case "warn", "warning":
-		return slog.LevelWarn
-	case "error":
-		return slog.LevelError
-	default:
-		return slog.LevelInfo
-	}
-}

cmd/relay/main.go

@@ -6,9 +6,9 @@ import (
 	"log/slog"
 	"os"
 	"os/signal"
-	"strings"
 	"syscall"
 
+	edgelogging "github.com/Rain-kl/Wavelet/internal/apps/edge/logging"
 	"github.com/Rain-kl/Wavelet/internal/apps/relay/config"
 	"github.com/Rain-kl/Wavelet/internal/apps/relay/frps"
 	"github.com/Rain-kl/Wavelet/internal/apps/relay/heartbeat"
@@ -19,10 +19,7 @@ import (
 )
 
 func main() {
-	// Setup simple structured logging
-	slog.SetDefault(slog.New(slog.NewTextHandler(os.Stdout, &slog.HandlerOptions{
-		Level: parseLevel(os.Getenv("LOG_LEVEL")),
-	})))
+	edgelogging.Setup(edgelogging.Options{})
 
 	configPath := flag.String("config", "./relay.json", "relay config path")
 	flag.Parse()
@@ -72,16 +69,3 @@ func main() {
 	}
 	slog.Info("relay process stopped")
 }
-
-func parseLevel(value string) slog.Level {
-	switch strings.ToLower(strings.TrimSpace(value)) {
-	case "debug":
-		return slog.LevelDebug
-	case "warn", "warning":
-		return slog.LevelWarn
-	case "error":
-		return slog.LevelError
-	default:
-		return slog.LevelInfo
-	}
-}