feat: Add unified LiteLLM API management with dashboard UI and CLI integration

- Create ccw-litellm Python package with AbstractEmbedder and AbstractLLMClient interfaces
- Add BaseEmbedder abstraction and factory pattern to codex-lens for pluggable backends
- Implement API Settings dashboard page for provider credentials and custom endpoints
- Add REST API routes for CRUD operations on providers and endpoints
- Extend CLI with --model parameter for custom endpoint routing
- Integrate existing context-cache for @pattern file resolution
- Add provider model registry with predefined models per provider type
- Include i18n translations (en/zh) for all new UI elements

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

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

ccw-litellm/tests/conftest.py

@@ -0,0 +1,11 @@
+from __future__ import annotations
+
+import sys
+from pathlib import Path
+
+
+def pytest_configure() -> None:
+    project_root = Path(__file__).resolve().parents[1]
+    src_dir = project_root / "src"
+    sys.path.insert(0, str(src_dir))
+