### What problem does this PR solve?
- Add comprehensive test suite for chunk operations including:
- Test files for create, list, retrieve, update, and delete chunks
- Authorization tests
- Batch operations tests
- Update test configurations and common utilities
- Validate `important_kwd` and `question_kwd` fields are lists in
chunk_app.py
- Reorganize imports and clean up duplicate code
### Type of change
- [x] Add test cases
### What problem does this PR solve?
- Add new test suite for document app with
create/list/parse/upload/remove tests
- Update API URLs to use version variable from config in HTTP and web
API tests
### Type of change
- [x] Add test cases
### What problem does this PR solve?
- Implement RAGFlowWebApiAuth class for web API authentication
- Add comprehensive test cases for KB CRUD operations
- Set up common fixtures and utilities in conftest.py
- Add helper functions in common.py for web API requests
The changes establish a complete testing framework for knowledge base
management via web API endpoints.
### Type of change
- [x] Add test case
