Fix SSE route dependency and align architecture docs

backend/app/domain/conversation/ports.py

@@ -0,0 +1,78 @@
+"""Define domain ports for conversation."""
+
+from __future__ import annotations
+
+from abc import ABC, abstractmethod
+from typing import Generator
+
+from app.domain.retrieval.models import RetrievedChunk
+
+from .models import AnswerResult, ConversationSession
+# Keep domain contracts explicit so adapters can swap implementations cleanly.
+
+
+
+class AnswerGenerator(ABC):
+    """Represent the Answer Generator type."""
+    @abstractmethod
+    def generate(
+        self,
+        *,
+        query: str,
+        retrieved_chunks: list[RetrievedChunk],
+        history: list[dict[str, str]] | None = None,
+        provider: str | None = None,
+        model: str | None = None,
+        prompt_template: str | None = None,
+    ) -> AnswerResult:
+        """Handle generate for the Answer Generator instance."""
+        pass
+
+    @abstractmethod
+    def stream_generate(
+        self,
+        *,
+        query: str,
+        retrieved_chunks: list[RetrievedChunk],
+        history: list[dict[str, str]] | None = None,
+        provider: str | None = None,
+        model: str | None = None,
+        prompt_template: str | None = None,
+    ) -> Generator[dict, None, AnswerResult]:
+        """Stream generate for the Answer Generator instance."""
+        pass
+
+
+class ConversationStore(ABC):
+    """Provide the Conversation Store store implementation."""
+    @abstractmethod
+    def create_session(self, metadata: dict | None = None) -> ConversationSession:
+        """Create session for the Conversation Store instance."""
+        pass
+
+    @abstractmethod
+    def get_session(self, session_id: str) -> ConversationSession | None:
+        """Return session for the Conversation Store instance."""
+        pass
+
+    @abstractmethod
+    def save_message(
+        self,
+        session_id: str,
+        *,
+        role: str,
+        content: str,
+        sources: list[dict] | None = None,
+    ) -> ConversationSession | None:
+        """Save message for the Conversation Store instance."""
+        pass
+
+    @abstractmethod
+    def delete_session(self, session_id: str) -> bool:
+        """Delete session for the Conversation Store instance."""
+        pass
+
+    @abstractmethod
+    def list_sessions(self) -> list[dict]:
+        """List sessions for the Conversation Store instance."""
+        pass