fix(agent-runner): package context for plugin execution

src/langbot/pkg/pipeline/msgtrun/truncators/round.py

@@ -3,6 +3,10 @@ from __future__ import annotations
 from .. import truncator
 import langbot_plugin.api.entities.builtin.pipeline.query as pipeline_query
 from ....agent.runner.config_migration import ConfigMigration
+from ....agent.runner.context_packager import (
+    get_legacy_max_round,
+    select_legacy_max_round_messages,
+)
 
 
 @truncator.truncator_class('round')
@@ -11,25 +15,15 @@ class RoundTruncator(truncator.Truncator):
 
     async def truncate(self, query: pipeline_query.Query) -> pipeline_query.Query:
         """截断"""
-        # max-round remains a pipeline-side trimming knob until token-budget
-        # based compaction replaces this stage.
         runner_id = ConfigMigration.resolve_runner_id(query.pipeline_config)
-        runner_config = ConfigMigration.resolve_runner_config(query.pipeline_config, runner_id) if runner_id else {}
-        max_round = runner_config.get('max-round', 10)
+        if runner_id:
+            runner_config = ConfigMigration.resolve_runner_config(query.pipeline_config, runner_id)
+        else:
+            runner_config = query.pipeline_config.get('msg-truncate', {}).get('round', {})
 
-        temp_messages = []
-
-        current_round = 0
-
-        # Traverse from back to front
-        for msg in query.messages[::-1]:
-            if current_round < max_round:
-                temp_messages.append(msg)
-                if msg.role == 'user':
-                    current_round += 1
-            else:
-                break
-
-        query.messages = temp_messages[::-1]
+        query.messages = select_legacy_max_round_messages(
+            query.messages,
+            get_legacy_max_round(runner_config),
+        )
 
         return query