feat: enhance agent management with session handling and UI improvements

backend/app/core/agent_auth.py

@@ -0,0 +1,51 @@
+from __future__ import annotations
+
+from dataclasses import dataclass
+from typing import Literal
+
+from fastapi import Depends, Header, HTTPException, status
+from sqlmodel import Session, col, select
+
+from app.core.agent_tokens import verify_agent_token
+from app.db.session import get_session
+from app.models.agents import Agent
+
+
+@dataclass
+class AgentAuthContext:
+    actor_type: Literal["agent"]
+    agent: Agent
+
+
+def _find_agent_for_token(session: Session, token: str) -> Agent | None:
+    agents = list(
+        session.exec(select(Agent).where(col(Agent.agent_token_hash).is_not(None)))
+    )
+    for agent in agents:
+        if agent.agent_token_hash and verify_agent_token(token, agent.agent_token_hash):
+            return agent
+    return None
+
+
+def get_agent_auth_context(
+    agent_token: str | None = Header(default=None, alias="X-Agent-Token"),
+    session: Session = Depends(get_session),
+) -> AgentAuthContext:
+    if not agent_token:
+        raise HTTPException(status_code=status.HTTP_401_UNAUTHORIZED)
+    agent = _find_agent_for_token(session, agent_token)
+    if agent is None:
+        raise HTTPException(status_code=status.HTTP_401_UNAUTHORIZED)
+    return AgentAuthContext(actor_type="agent", agent=agent)
+
+
+def get_agent_auth_context_optional(
+    agent_token: str | None = Header(default=None, alias="X-Agent-Token"),
+    session: Session = Depends(get_session),
+) -> AgentAuthContext | None:
+    if not agent_token:
+        return None
+    agent = _find_agent_for_token(session, agent_token)
+    if agent is None:
+        raise HTTPException(status_code=status.HTTP_401_UNAUTHORIZED)
+    return AgentAuthContext(actor_type="agent", agent=agent)