refactor: extract should_include_path to utils module to resolve circular import between indexer and attachment_indexer

backend/attachment_indexer.py

@@ -4,7 +4,7 @@ from pathlib import Path
 from typing import Dict, List, Optional, Set
 import threading
 
-from backend.indexer import _should_include_path
+from backend.utils import should_include_path
 
 logger = logging.getLogger("obsigate.attachment_indexer")
 
@@ -67,7 +67,7 @@ def _scan_vault_attachments(vault_name: str, vault_path: str, vault_cfg: dict =
         for fpath in vault_root.rglob("*"):
             # Check if path should be included based on hidden files configuration
             rel_parts = fpath.relative_to(vault_root).parts
-            if not _should_include_path(rel_parts, vault_cfg):
+            if not should_include_path(rel_parts, vault_cfg):
                 continue
             
             # Only process files