Update platform.py

Author: Jason2866

platform.py

@@ -56,6 +56,29 @@ def configure_default_packages(self, variables, targets):
         board_sdkconfig = variables.get("board_espidf.custom_sdkconfig", board_config.get("espidf.custom_sdkconfig", ""))
         frameworks = variables.get("pioframework", [])
 
+        def _lazy_framework_validation(self, variables):
+            """Perform framework validation only when actually needed"""
+            if not hasattr(self, '_framework_validated'):
+                frameworks = variables.get("pioframework", [])
+        
+                # Only validate if we have sufficient context
+                if (variables.get("board") and 
+                    variables.get("project_dir") and 
+                    not frameworks):
+    
+                    self._show_framework_warning()
+    
+                self._framework_validated = True
+
+        def _show_framework_warning(self):
+            """Show framework warning without terminating early setup"""
+            warning_msg = (
+                "\n⚠️  WARNING: No framework specified in platformio.ini\n"
+                "   Add 'framework = arduino' or 'framework = espidf'\n"
+                "   Build may fail without proper framework configuration.\n"
+            )
+            print(warning_msg, file=sys.stderr)
+
         def install_tool(TOOL, retry_count=0):
             self.packages[TOOL]["optional"] = False
             TOOL_PATH = os.path.join(ProjectConfig.get_instance().get("platformio", "packages_dir"), TOOL)