Refactor document handling and update Milvus collection settings

- Removed multiple failed document entries from `documents.json`.
- Added a new document entry with updated metadata and changed the index name to `regulations_dense_1024_v2`.
- Updated architecture documentation to reflect changes in the Milvus collection name.
- Adjusted requirements by removing the sqlalchemy dependency.
- Modified test cases to align with new document structure and naming conventions.
- Introduced a new test file for Milvus vector index runtime recovery and error handling.
- Updated assertions in various test files to ensure compatibility with the new schema.

backend/app/api/routes/knowledge.py

@@ -29,14 +29,19 @@ async def search_knowledge(request: SearchRequest):
         results=[
             SearchResultItem(
                 id=index + 1,
-                content=item.content,
+                content=item.text,
                 score=item.score,
                 metadata={
                     "doc_id": item.doc_id,
-                    "doc_name": item.doc_name,
+                    "doc_title": item.doc_title,
                     "chunk_id": item.chunk_id,
+                    "chunk_type": item.chunk_type,
                     "section_title": item.section_title,
-                    "page_number": item.page_number,
+                    "page_start": item.page_start,
+                    "page_end": item.page_end,
+                    "section_level": item.section_level,
+                    "chunk_index": item.chunk_index,
+                    "piece_index": item.piece_index,
                     **item.metadata,
                 },
             )