feat(loadtest): sync add real 500-session capacity harness

internal/rpc/rate_limit.go

@@ -67,6 +67,13 @@ func (r *Router) checkSendRateLimit(ctx context.Context, userID int64, cost int)
 	}
 	allowed, retryAfter, err := r.deps.Limiter.AllowN(ctx, sendRateLimitKeyPrefix+strconv.FormatInt(userID, 10), cost, limit, window)
 	if err != nil {
+		r.log.Warn("message send rate limiter failed",
+			append(r.contextLogFields(ctx),
+				zap.Error(err),
+				zap.Int("cost", cost),
+				zap.Int("limit", limit),
+				zap.Duration("window", window),
+			)...)
 		return internalErr()
 	}
 	if allowed {

internal/rpc/router_dispatch_test.go

@@ -66,8 +66,12 @@ func TestDispatchUnwrapsWrappers(t *testing.T) {
 	if cfg.ThisDC != dc {
 		t.Fatalf("ThisDC = %d, want %d", cfg.ThisDC, dc)
 	}
-	if len(cfg.DCOptions) != 0 {
-		t.Fatalf("DCOptions = %+v, want empty (client uses pinned static address)", cfg.DCOptions)
+	if len(cfg.DCOptions) != 1 {
+		t.Fatalf("DCOptions = %+v, want one reconnect route", cfg.DCOptions)
+	}
+	option := cfg.DCOptions[0]
+	if option.ID != dc || option.IPAddress != ip || option.Port != port || option.Ipv6 || option.MediaOnly || option.CDN {
+		t.Fatalf("DCOptions[0] = %+v, want primary dc=%d at %s:%d", option, dc, ip, port)
 	}
 }
 

internal/rpc/send_replay.go

@@ -5,6 +5,7 @@ import (
 	"crypto/sha256"
 
 	"github.com/iamxvbaba/td/tg"
+	"go.uber.org/zap"
 
 	"telesrv/internal/domain"
 )
@@ -46,6 +47,11 @@ func (r *Router) lookupOutgoingReplay(ctx context.Context, userID int64, peer do
 			IdempotencyFingerprint: fingerprint,
 		})
 		if err != nil {
+			r.log.Warn("private send replay lookup failed",
+				append(r.contextLogFields(ctx),
+					zap.Error(err),
+					zap.Int64("recipient_user_id", peer.ID),
+				)...)
 			return outgoingReplayLookup{checked: true}, messageSendErr(err)
 		}
 		return outgoingReplayLookup{private: res, found: found, checked: true}, nil