feat(flow): auto-resolve authentik sub and improve admin dropdown UX

app/services/authentik_admin_service.py

@@ -12,6 +12,7 @@ from app.core.config import Settings
 class AuthentikSyncResult:
     user_id: int
     action: str
+    authentik_sub: str | None = None
 
 
 class AuthentikAdminService:
@@ -66,10 +67,14 @@ class AuthentikAdminService:
                 patch_resp = client.patch(f"/api/v3/core/users/{user_pk}/", json=payload)
                 if patch_resp.status_code >= 400:
                     raise HTTPException(status_code=502, detail="authentik_update_failed")
-                return AuthentikSyncResult(user_id=user_pk, action="updated")
+                return AuthentikSyncResult(user_id=user_pk, action="updated", authentik_sub=existing.get("uid"))
 
             create_resp = client.post("/api/v3/core/users/", json=payload)
             if create_resp.status_code >= 400:
                 raise HTTPException(status_code=502, detail="authentik_create_failed")
             created = create_resp.json()
-            return AuthentikSyncResult(user_id=int(created["pk"]), action="created")
+            return AuthentikSyncResult(
+                user_id=int(created["pk"]),
+                action="created",
+                authentik_sub=created.get("uid"),
+            )