add block diagrams for celery sse communication

2026/celery/slides/02-progressbar.md

@@ -131,6 +131,13 @@ https://docs.celeryq.dev/en/main/reference/celery.events.html
 
 
 
+### Coté Worker
+- celery.events.EventDispatcher 📢
+- celery.events.EventReceiver 👂
+
+
+
+
 ### Coté Worker
 <!-- .slide: data-auto-animate -->
 
@@ -187,10 +194,10 @@ class PtfTask(AbortableTask):
 ```python
 @shared_task(name="crawler.tasks.toto", base=PtfTask, bind=True)
 def print_toto(self, toto = "toto"):   
-    
+    meta = {"current": 0, "total": len(toto)}
     # Initialize progress bar at 0
     self.update_state(
-        meta={"current": index, "total": len(toto)},
+        meta=meta,
         state=states.STARTED,
     )
     
@@ -199,8 +206,9 @@ def print_toto(self, toto = "toto"):
         print(letter)
         
         # Update progress bar
+        meta["current"] = index
         self.update_state(
-            meta={"current": index, "total": len(toto)},
+            meta=meta,
             state=states.STARTED,
         )
 ```