Show author_agent in LineagePage checkpoint cards

backend/app/api/routes/lineage.py

@@ -80,6 +80,7 @@ class CheckpointNode(BaseModel):
     created_at: datetime
     summary: str
     objective: str
+    author_agent: Optional[str] = None
 
     model_config = {"from_attributes": True}
 
@@ -365,6 +366,7 @@ def get_lineage(space_id: uuid.UUID, db: Session = Depends(get_db)):
             created_at=c.created_at,
             summary=c.summary or "",
             objective=c.objective or "",
+            author_agent=c.author_agent,
         )
         for c in commits
     ]

frontend/src/pages/LineagePage.tsx

@@ -313,6 +313,11 @@ function CheckpointCard({
         <div className="flex-1 min-w-0">
           <div className="flex items-center gap-2 mb-0.5">
             <code className="text-[10px] text-blue-400 font-mono">{checkpoint.commit_hash.slice(0, 7)}</code>
+            {checkpoint.author_agent && (
+              <span className="text-[10px] text-gray-500 font-mono border border-gray-700 px-1.5 py-px rounded">
+                {checkpoint.author_agent}
+              </span>
+            )}
             <span className="text-[10px] text-gray-600">{fmt(checkpoint.created_at)}</span>
           </div>
           <p className="text-xs text-gray-300 font-medium truncate">{checkpoint.message}</p>

frontend/src/types/index.ts

@@ -199,6 +199,7 @@ export interface CheckpointNode {
   created_at: string;
   summary: string;
   objective: string;
+  author_agent: string | null;
 }
 
 export interface SessionNode {