feat(bot/extension/watcher): Discord 아티팩트 알림 개선 — 파일 첨부 전송, truncation 확대, 동적 .md 감시

watcher.py

@@ -110,8 +110,14 @@ class BrainEventHandler(FileSystemEventHandler):
         return True
 
     def _is_watched_file(self, file_name: str) -> bool:
-        """Strict filter: only watch primary artifact files."""
-        return file_name in Config.WATCHED_FILES
+        """Filter: watch primary artifact files + any file matching watched extensions."""
+        if file_name in Config.WATCHED_FILES:
+            return True
+        # Extension-based matching (e.g., any .md file in conversation dir)
+        ext = Path(file_name).suffix
+        if ext and ext in Config.WATCHED_EXTENSIONS:
+            return True
+        return False
 
     def _emit(self, event: BrainEvent):
         self.loop.call_soon_threadsafe(self.event_queue.put_nowait, event)
@@ -142,9 +148,17 @@ class BrainEventHandler(FileSystemEventHandler):
         if not conv_id:
             return
 
+        # Exclude files in .system_generated subdirectory (AG internal logs)
+        try:
+            relative = path.relative_to(Config.BRAIN_PATH / conv_id)
+            if '.system_generated' in relative.parts:
+                return
+        except ValueError:
+            pass
+
         file_name = path.name
 
-        # STRICT filter: only primary artifacts
+        # Filter: watched files by name or extension
         if not self._is_watched_file(file_name):
             return