fix(VirtualStream): Fix stream closing behavior to correctly handle closing bits

ts/classes.virtualstream.ts

@@ -1,6 +1,9 @@
 import * as plugins from './plugins.js';
 import { TypedRouter } from './classes.typedrouter.js';
 
+
+const closingBit: any = '#############CLOSING BIT#############';
+
 export interface ICommFunctions {
   sendMethod?: (
     sendPayload: plugins.typedRequestInterfaces.IStreamRequest
@@ -278,7 +281,7 @@ export class VirtualStream<T = Uint8Array> implements plugins.typedRequestInterf
           cycleId: streamTrArg.request.cycleId,
           cycle: 'response',
           mainPurpose: 'chunk',
-          next: this.sendBackpressuredArray.data.length > 1,
+          next: this.sendBackpressuredArray.data.length > 1, // 1 and not 0 because we call shift a few lines down
           backpressure: !this.receiveBackpressuredArray.checkSpaceAvailable(),
           chunkData: this.sendBackpressuredArray.shift(),
         };
@@ -392,7 +395,7 @@ export class VirtualStream<T = Uint8Array> implements plugins.typedRequestInterf
       streamIsDone = done;
     }
     if (closeAfterReading) {
-      await this.close();
+      await this.close(true);
     }
   }
 
@@ -400,7 +403,7 @@ export class VirtualStream<T = Uint8Array> implements plugins.typedRequestInterf
     const writer = writableStreamArg.getWriter();
     while(this.keepAlive || this.receiveBackpressuredArray.checkHasItems()) {
       const value = await this.fetchData();
-      if (value === null) {
+      if (value === closingBit) {
         writableStreamArg.close();
         break;
       }
@@ -408,8 +411,15 @@ export class VirtualStream<T = Uint8Array> implements plugins.typedRequestInterf
     }
   }
 
-  public async close() {
-    this.sendData(null);
+  /**
+   * closes the stream
+   * if sendClosingBitArg is true, the stream will send a closing bit
+   * @param sendClosingBitArg 
+   */
+  public async close(sendClosingBitArg = false) {
+    if (sendClosingBitArg) {
+      this.sendData(closingBit);
+    }
     this.keepAlive = false;
   }
 }