feat(ext): Add docname to keywords

Author: SilverRainZ

src/sphinxnotes/snippet/ext.py

@@ -57,7 +57,7 @@ def extract_excerpt(s: Snippet) -> str:
 
 
 def extract_keywords(s: Snippet) -> List[str]:
- keywords = []
+ keywords = [s.docname]
  # TODO: Deal with more snippet
  if isinstance(s, WithTitle) and s.title is not None:
  keywords.extend(extractor.extract(s.title.text, strip_stopwords=False))