### What problem does this PR solve?
This PR adds missing web API tests (system, search, KB, LLM, plugin,
connector). It also addresses a contract mismatch that was causing test
failures: metadata updates did not persist new keys (update‑only
behavior).
### Type of change
- [x] Bug Fix (non-breaking change which fixes an issue)
- [x] New Feature (non-breaking change which adds functionality)
- [x] Other (please describe): Test coverage expansion and test helper
instrumentation
### What problem does this PR solve?
Introduced gpu profile in .env
Added Dockerfile_tei
fix datrie
Removed LIGHTEN flag
### Type of change
- [x] Documentation Update
- [x] Refactoring
### 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