fix(delivery): prevent throttle reset timer from firing after stop and avoid scheduling duplicate timers

ts/00_commitinfo_data.ts

@@ -3,6 +3,6 @@
  */
 export const commitinfo = {
   name: '@push.rocks/smartmta',
-  version: '5.2.2',
+  version: '5.2.3',
   description: 'A high-performance, enterprise-grade Mail Transfer Agent (MTA) built from scratch in TypeScript with Rust acceleration.'
 }

ts/mail/delivery/classes.delivery.system.ts

@@ -108,6 +108,7 @@ export class MultiModeDeliverySystem extends EventEmitter {
   private activeDeliveries: Set<string> = new Set();
   private running: boolean = false;
   private throttled: boolean = false;
+  private throttleResetTimer: ReturnType<typeof setTimeout> | null = null;
   private rateLimitLastCheck: number = Date.now();
   private rateLimitCounter: number = 0;
   private emailServer?: UnifiedEmailServer;
@@ -211,7 +212,13 @@ export class MultiModeDeliverySystem extends EventEmitter {
     }
     
     this.running = false;
-    
+
+    // Clear throttle reset timer to prevent it firing after stop
+    if (this.throttleResetTimer) {
+      clearTimeout(this.throttleResetTimer);
+      this.throttleResetTimer = null;
+    }
+
     // Wait for active deliveries to complete
     if (this.activeDeliveries.size > 0) {
       logger.log('info', `Waiting for ${this.activeDeliveries.size} active deliveries to complete`);
@@ -776,7 +783,11 @@ export class MultiModeDeliverySystem extends EventEmitter {
       
       // Schedule throttle reset
       const resetDelay = 60000 - elapsed;
-      setTimeout(() => {
+      if (this.throttleResetTimer) {
+        clearTimeout(this.throttleResetTimer);
+      }
+      this.throttleResetTimer = setTimeout(() => {
+        this.throttleResetTimer = null;
         this.throttled = false;
         this.rateLimitLastCheck = Date.now();
         this.rateLimitCounter = 0;