fix: 仅向已握手连接推送并拆分调度循环

internal/app/message/app.go

@@ -90,10 +90,16 @@ type App struct {
 	met   *metrics.Registry
 
 	mu            sync.Mutex
-	largeSem      chan struct{}
-	largeHeld     map[string]bool
 	pendingRevoke []revokeJob
 	repushTimers  map[string]*time.Timer
+	workers       map[string]*pushWorker
+	handshook     map[string]port.ConnID
+	rcptInflight  map[string]map[int64]int64 // connID → receiptID → 推送时刻 ms
+
+	dispatchCh chan struct{}
+	loopWG     sync.WaitGroup
+	lastPurge  time.Time
+	purgeMu    sync.Mutex
 }
 
 // Option 配置 App。
@@ -142,13 +148,15 @@ func New(db *store.DB, lim Limits, hash auth.HashPool, opts ...Option) *App {
 		lim.GraceSeconds = 60
 	}
 	a := &App{
-		db:        db,
-		lim:       lim,
-		hash:      hash,
-		nowFn:     time.Now,
-		rates:     newRateLimiter(lim.RequestsPerSecond, lim.RequestBurst),
-		largeSem:  make(chan struct{}, maxLargeInflight),
-		largeHeld: make(map[string]bool),
+		db:           db,
+		lim:          lim,
+		hash:         hash,
+		nowFn:        time.Now,
+		rates:        newRateLimiter(lim.RequestsPerSecond, lim.RequestBurst),
+		workers:      make(map[string]*pushWorker),
+		handshook:    make(map[string]port.ConnID),
+		rcptInflight: make(map[string]map[int64]int64),
+		dispatchCh:   make(chan struct{}, 1),
 	}
 	for _, opt := range opts {
 		opt(a)