Enhance AI handler logging and add main PR language attribute to AI handler in various tools

pr_agent/tools/pr_add_docs.py

@@ -26,6 +26,8 @@ class PRAddDocs:
         )
 
         self.ai_handler = ai_handler()
+        self.ai_handler.main_pr_language = self.main_language
+
         self.patches_diff = None
         self.prediction = None
         self.cli_mode = cli_mode