Added configuration option to control publishing review progress

This can be useful in a few situations:
1. To reduce the number of GitHub API calls (thus avoiding hitting the rate limit)
2. When the trigger for the agent is an external process (e.g. some external CI job), so there is no need to publish a message like "preparing review..." because it's not a part of a natual conversation with the user

pr_agent/git_providers/github_provider.py

@@ -50,6 +50,9 @@ class GithubProvider(GitProvider):
         # self.pr.create_issue_comment(pr_comment)
 
     def publish_comment(self, pr_comment: str, is_temporary: bool = False):
+        if is_temporary and not settings.config.publish_output_progress:
+            logging.debug(f"Skipping publish_comment for temporary comment: {pr_comment}")
+            return
         response = self.pr.create_issue_comment(pr_comment)
         if hasattr(response, "user") and hasattr(response.user, "login"):
             self.github_user_id = response.user.login
@@ -140,7 +143,7 @@ class GithubProvider(GitProvider):
 
     def remove_initial_comment(self):
         try:
-            for comment in self.pr.comments_list:
+            for comment in getattr(self.pr, 'comments_list', []):
                 if comment.is_temporary:
                     comment.delete()
         except Exception as e:

pr_agent/settings/configuration.toml

@@ -2,6 +2,7 @@
 model="gpt-4-0613"
 git_provider="github"
 publish_output=true
+publish_output_progress=true
 verbosity_level=0 # 0,1,2
 
 [pr_reviewer]