fix: 全隧道模式跳过无意义的CIDR URL下载

全隧道模式下before-proxy、after-proxy和手动刷新三处仍会从URL
下载CIDR表，但下载结果永远不会被使用。添加ModeFull短路返回，
消除无意义的网络请求和连接延迟。

bump version to 0.6.9

internal/vpn/session.go

@@ -197,7 +197,7 @@ func (sm *SessionManager) run(ctx context.Context, cfg SessionConfig) {
 	// to avoid consuming the server's 30s ReadyTimeout budget.
 	var beforeCIDRs []string
 	allURLSources := append(append([]model.CIDRURLSource{}, cfg.CIDRV4URLs...), cfg.CIDRV6URLs...)
-	if len(allURLSources) > 0 {
+	if len(allURLSources) > 0 && cfg.RoutingMode != route.ModeFull {
 		sm.stats.SetConnectStep("fetch_cidrs")
 		sm.setState(stats.StateConnecting)
 		log.L().Info("fetching before-proxy CIDR lists", "url_count", len(allURLSources))
@@ -588,6 +588,9 @@ func (sm *SessionManager) setupTUN(init protocol.InitMessage, cfg SessionConfig,
 // (via the tunnel) and dynamically adds their routes to the route
 // manager. This is called in a goroutine after the data plane is up.
 func (sm *SessionManager) fetchAfterProxyCIDRs(ctx context.Context, cfg SessionConfig) {
+	if cfg.RoutingMode == route.ModeFull {
+		return
+	}
 	allURLSources := append(append([]model.CIDRURLSource{}, cfg.CIDRV4URLs...), cfg.CIDRV6URLs...)
 	// Count only "after" sources for logging.
 	afterCount := 0
@@ -659,6 +662,10 @@ func (sm *SessionManager) RefreshCIDRs() {
 		return
 	}
 
+	if cfg.RoutingMode == route.ModeFull {
+		return
+	}
+
 	// Use a background context with 30s timeout so the refresh works
 	// even if the session context is in a weird state.
 	refreshCtx, cancel := context.WithTimeout(context.Background(), 30*time.Second)