### What problem does this PR solve?

- Update chat assistant tests to use dataset.id directly in payloads
- Enhance document parsing tests with better condition checking
- Add explicit type hints and improve timeout handling

Action_7556

### Type of change

- [x] Bug Fix (non-breaking change which fixes an issue)

### What problem does this PR solve?

- Consolidate HTTP API test fixtures using batch operations
(batch_add_chunks, batch_create_chat_assistants)
- Fix fixture initialization order in clear_session_with_chat_assistants
- Add new SDK API test suite for session management
(create/delete/list/update)

### Type of change

- [x] Add test cases
- [x] Refactoring

### What problem does this PR solve?

- Implement new SDK API test cases for chat assistant CRUD operations
- Enhance HTTP API concurrent tests to use as_completed for better
reliability

### Type of change

- [x] Add test cases
- [x] Refactoring