feat!: migrate to OpenAI native tool calls and fix circular deps (#fuck-gemini)

- Fix circular dependencies in agent/tools
- Migrate from custom JSON to OpenAI tool calls format
- Add async streaming (step_stream, complete_stream)
- Simplify prompt system and remove token counting
- Add 5 new API endpoints (/health, /v1/models, /api/memory/*)
- Add 3 new tools (get_torrent_by_index, add_torrent_by_index, set_language)
- Fix all 500 tests and add coverage config (80% threshold)
- Add comprehensive docs (README, pytest guide)

BREAKING: LLM interface changed, memory injection via get_memory()

domain/shared/__init__.py

@@ -1,6 +1,7 @@
 """Shared kernel - Common domain concepts used across subdomains."""
+
 from .exceptions import DomainException, ValidationError
-from .value_objects import ImdbId, FilePath, FileSize
+from .value_objects import FilePath, FileSize, ImdbId
 
 __all__ = [
     "DomainException",