Fix type validation in ToolUsageFinishedEvent to accept any result type

Co-Authored-By: Joe Moura <joao@crewai.com>

src/crewai/tools/tool_usage.py

@@ -494,7 +494,7 @@ class ToolUsage:
 
     def on_tool_use_finished(
         self, tool: Any, tool_calling: ToolCalling, from_cache: bool, started_at: float, 
-        result: Union[str, dict, None] = None
+        result: Any = None
     ) -> None:
         """Handle tool usage completion event.
         

src/crewai/utilities/events/tool_usage_events.py

@@ -34,7 +34,7 @@ class ToolUsageFinishedEvent(ToolUsageEvent):
     started_at: datetime
     finished_at: datetime
     from_cache: bool = False
-    result: Union[str, dict, None] = None  # Tool execution result
+    result: Any = None  # Tool execution result
     type: str = "tool_usage_finished"