feat: add boards and tasks management endpoints

backend/app/models/agents.py

@@ -0,0 +1,18 @@
+from __future__ import annotations
+
+from datetime import datetime
+from uuid import UUID, uuid4
+
+from sqlmodel import Field, SQLModel
+
+
+class Agent(SQLModel, table=True):
+    __tablename__ = "agents"
+
+    id: UUID = Field(default_factory=uuid4, primary_key=True)
+    name: str = Field(index=True)
+    status: str = Field(default="online", index=True)
+    openclaw_session_id: str | None = Field(default=None, index=True)
+    last_seen_at: datetime = Field(default_factory=datetime.utcnow)
+    created_at: datetime = Field(default_factory=datetime.utcnow)
+    updated_at: datetime = Field(default_factory=datetime.utcnow)