fix: share event metadata setup between emit and aemit

Extract _prepare_event to set previous_event_id, triggered_by_event_id,
emission_sequence, parent/child scoping, and event_record tracking.
Both emit and aemit now call it, fixing aemit's missing metadata.

lib/crewai/src/crewai/events/event_bus.py

@@ -435,32 +435,8 @@ class CrewAIEventsBus:
             if level_async:
                 await self._acall_handlers(source, event, level_async)
 
-    def emit(self, source: Any, event: BaseEvent) -> Future[None] | None:
-        """Emit an event to all registered handlers.
-
-        If handlers have dependencies (registered with depends_on), they execute
-        in dependency order. Otherwise, handlers execute as before (sync in thread
-        pool, async fire-and-forget).
-
-        Stream chunk events always execute synchronously to preserve ordering.
-
-        Args:
-            source: The emitting object
-            event: The event instance to emit
-
-        Returns:
-            Future that completes when handlers finish. Returns:
-            - Future for sync-only handlers (ThreadPoolExecutor future)
-            - Future for async handlers or mixed handlers (asyncio future)
-            - Future for dependency-managed handlers (asyncio future)
-            - None if no handlers or sync stream chunk events
-
-        Example:
-            >>> future = crewai_event_bus.emit(source, event)
-            >>> if future:
-            ...     await asyncio.wrap_future(future)  # In async test
-            ...     # or future.result(timeout=5.0) in sync code
-        """
+    def _prepare_event(self, source: Any, event: BaseEvent) -> None:
+        """Set event metadata, register the source entity, and record the event."""
         if (
             getattr(source, "entity_type", None) in ("flow", "crew", "agent")
             and id(source) not in self._registered_entity_ids
@@ -494,6 +470,34 @@ class CrewAIEventsBus:
         if self._runtime_state is not None:
             self._runtime_state.event_record.add(event)
 
+    def emit(self, source: Any, event: BaseEvent) -> Future[None] | None:
+        """Emit an event to all registered handlers.
+
+        If handlers have dependencies (registered with depends_on), they execute
+        in dependency order. Otherwise, handlers execute as before (sync in thread
+        pool, async fire-and-forget).
+
+        Stream chunk events always execute synchronously to preserve ordering.
+
+        Args:
+            source: The emitting object
+            event: The event instance to emit
+
+        Returns:
+            Future that completes when handlers finish. Returns:
+            - Future for sync-only handlers (ThreadPoolExecutor future)
+            - Future for async handlers or mixed handlers (asyncio future)
+            - Future for dependency-managed handlers (asyncio future)
+            - None if no handlers or sync stream chunk events
+
+        Example:
+            >>> future = crewai_event_bus.emit(source, event)
+            >>> if future:
+            ...     await asyncio.wrap_future(future)  # In async test
+            ...     # or future.result(timeout=5.0) in sync code
+        """
+        self._prepare_event(source, event)
+
         event_type = type(event)
 
         with self._rwlock.r_locked():
@@ -592,14 +596,7 @@ class CrewAIEventsBus:
             source: The object emitting the event
             event: The event instance to emit
         """
-        if (
-            getattr(source, "entity_type", None) in ("flow", "crew", "agent")
-            and id(source) not in self._registered_entity_ids
-        ):
-            self.register_entity(source)
-
-        if self._runtime_state is not None:
-            self._runtime_state.event_record.add(event)
+        self._prepare_event(source, event)
 
         event_type = type(event)