fix: Add async/await, PDF metadata, and type safety fixes

This commit addresses multiple issues with async operations, PDF metadata
extraction, and type safety in document processing and search.

## Async/Await Fixes
- processor.py:259 - Added await for chunker.chunk_text(content)
- processor.py:270 - Added await for bm25_service.encode_batch(chunk_texts)
- tests/unit/test_document_chunker.py - Converted all 12 test methods to async

## PDF Metadata Enhancement
- pymupdf.py:143 - Added file_size metadata extraction
- pymupdf.py:145-206 - Refactored to extract text page-by-page
  - Manually loop through pages instead of using page_chunks=True
  - Generate page_boundaries metadata for precise page tracking
  - Works around pymupdf.layout.activate() breaking page_chunks=True
- processor.py:32-66 - Added assign_page_numbers() helper function
  - Assigns page numbers to chunks based on overlap with page boundaries
  - Handles chunks spanning multiple pages
- processor.py:298-300 - Call assign_page_numbers() for PDF files

## Type Safety Fixes
- bm25_hybrid.py:184 - Removed int() conversion of doc_id
- semantic.py:131 - Removed int() conversion of doc_id
- viz_routes.py:275 - Removed int() conversion of doc_id
- Added comments documenting that doc_id can be int (notes) or str (file paths)

## Testing
- All 18 tests passing (12 unit + 6 integration)
- No type errors in modified files
- Container logs show successful processing
- Vector viz searches working correctly

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

nextcloud_mcp_server/search/bm25_hybrid.py

@@ -181,7 +181,8 @@ class BM25HybridSearchAlgorithm(SearchAlgorithm):
         results = []
 
         for result in search_response.points:
-            doc_id = int(result.payload["doc_id"])
+            # doc_id can be int (notes) or str (files - file paths)
+            doc_id = result.payload["doc_id"]
             doc_type = result.payload.get("doc_type", "note")
             doc_key = (doc_id, doc_type)
 

nextcloud_mcp_server/search/semantic.py

@@ -128,7 +128,8 @@ class SemanticSearchAlgorithm(SearchAlgorithm):
         results = []
 
         for result in search_response.points:
-            doc_id = int(result.payload["doc_id"])
+            # doc_id can be int (notes) or str (files - file paths)
+            doc_id = result.payload["doc_id"]
             doc_type = result.payload.get("doc_type", "note")
             doc_key = (doc_id, doc_type)