fix: add status field to service list/detail APIs, unify observeStats retry pattern, fix router bugs

- api: add fillServiceStatus helper and call it from getServiceList/getService
  so status field appears in service list and detail API responses
- observeStats: unify retry pattern across all 9 handlers (http, http2, masque,
  relay, router, socks4, socks5, tungo, tunnel) — buffer events on failure,
  continue to skip fresh collection, clear on success; fix event-loss bug
  where interim events were dropped during retry cycles
- handler/router: check WriteTo/Write return errors in associate.go and
  entrypoint.go; fix DelConnector and ConnectorPool.Del using RLock instead
  of Lock (write under read lock); remove unused fields t and cancel

handler/router/associate.go

@@ -52,7 +52,9 @@ func (h *routerHandler) handleAssociate(ctx context.Context, conn net.Conn, netw
 
 		if !rid.Equal(routerID) {
 			resp.Status = relay.StatusHostUnreachable
-			resp.WriteTo(conn)
+			if _, werr := resp.WriteTo(conn); werr != nil {
+				log.Error(werr)
+			}
 			err := fmt.Errorf("no route to host %s", host)
 			log.Error(err)
 			return err
@@ -62,7 +64,9 @@ func (h *routerHandler) handleAssociate(ctx context.Context, conn net.Conn, netw
 	uuid, err := uuid.NewRandom()
 	if err != nil {
 		resp.Status = relay.StatusInternalServerError
-		resp.WriteTo(conn)
+		if _, werr := resp.WriteTo(conn); werr != nil {
+			log.Error(werr)
+		}
 		return
 	}
 	connectorID := relay.NewConnectorID(uuid[:])
@@ -72,7 +76,9 @@ func (h *routerHandler) handleAssociate(ctx context.Context, conn net.Conn, netw
 			ID: connectorID,
 		},
 	)
-	resp.WriteTo(conn)
+	if _, werr := resp.WriteTo(conn); werr != nil {
+		log.Error(werr)
+	}
 
 	conn = &packetConn{conn}
 
@@ -203,7 +209,9 @@ func (h *routerHandler) handlePacket(ctx context.Context, data []byte, routerID
 
 	if c := h.pool.Get(routerID, route.Gateway); c != nil {
 		if w := c.Writer(); w != nil {
-			w.Write(data)
+			if _, werr := w.Write(data); werr != nil {
+				log.Error(werr)
+			}
 		}
 		return nil
 	}
@@ -231,7 +239,9 @@ func (h *routerHandler) handlePacket(ctx context.Context, data []byte, routerID
 	req.WriteTo(&buf)
 	buf.Write(data)
 
-	h.epConn.WriteTo(buf.Bytes(), raddr)
+	if _, werr := h.epConn.WriteTo(buf.Bytes(), raddr); werr != nil {
+		log.Error(werr)
+	}
 
 	return nil
 }

handler/router/entrypoint.go

@@ -48,7 +48,9 @@ func (h *routerHandler) handleEntrypoint(log logger.Logger) error {
 
 			if c := h.pool.Get(routerID, gateway); c != nil {
 				if w := c.Writer(); w != nil {
-					w.Write(buf[nn:])
+					if _, werr := w.Write(buf[nn:]); werr != nil {
+						log.Error(werr)
+					}
 				}
 			}
 

handler/router/handler.go

@@ -273,17 +273,22 @@ func (h *routerHandler) observeStats(ctx context.Context) {
 	for {
 		select {
 		case <-ticker.C:
+			// Try to flush any buffered events from a previous failed attempt.
 			if len(events) > 0 {
-				if err := h.options.Observer.Observe(ctx, events); err == nil {
-					events = nil
+				if err := h.options.Observer.Observe(ctx, events); err != nil {
+					continue
 				}
-				break
 			}
 
+			// Collect and send fresh events.
 			evs := h.stats.Events()
-			if err := h.options.Observer.Observe(ctx, evs); err != nil {
-				events = evs
+			if len(evs) > 0 {
+				if err := h.options.Observer.Observe(ctx, evs); err != nil {
+					events = evs
+					continue
+				}
 			}
+			events = nil
 
 		case <-ctx.Done():
 			return

handler/router/router.go

@@ -1,10 +1,8 @@
 package router
 
 import (
-	"context"
 	"io"
 	"sync"
-	"time"
 
 	"github.com/go-gost/core/logger"
 	"github.com/go-gost/relay"
@@ -76,7 +74,6 @@ type Router struct {
 	node       string
 	id         relay.TunnelID
 	connectors map[string][]*Connector
-	t          time.Time
 	close      chan struct{}
 	mu         sync.RWMutex
 }
@@ -86,7 +83,6 @@ func NewRouter(node string, rid relay.TunnelID) *Router {
 		node:       node,
 		id:         rid,
 		connectors: make(map[string][]*Connector),
-		t:          time.Now(),
 		close:      make(chan struct{}),
 	}
 	return r
@@ -139,8 +135,8 @@ func (r *Router) GetConnector(host string) *Connector {
 }
 
 func (r *Router) DelConnector(host string, cid relay.ConnectorID) {
-	r.mu.RLock()
-	defer r.mu.RUnlock()
+	r.mu.Lock()
+	defer r.mu.Unlock()
 
 	connectors := r.connectors[host]
 	for i, c := range connectors {
@@ -174,7 +170,6 @@ type ConnectorPool struct {
 	node    string
 	routers map[relay.TunnelID]*Router
 	mu      sync.RWMutex
-	cancel  context.CancelFunc
 }
 
 func NewConnectorPool(node string) *ConnectorPool {
@@ -219,8 +214,8 @@ func (p *ConnectorPool) Del(rid relay.TunnelID, host string, cid relay.Connector
 		return
 	}
 
-	p.mu.RLock()
-	defer p.mu.RUnlock()
+	p.mu.Lock()
+	defer p.mu.Unlock()
 
 	r := p.routers[rid]
 	if r == nil {
@@ -235,10 +230,6 @@ func (p *ConnectorPool) Close() error {
 		return nil
 	}
 
-	if p.cancel != nil {
-		p.cancel()
-	}
-
 	p.mu.Lock()
 	defer p.mu.Unlock()