Expose manual-member flag in admin overview (uses existing MANUAL_MEMBERS set)

app/main.py

@@ -1658,6 +1658,7 @@ async def admin_overview(request: Request):
                 "username": usernames.get(user_id),
                 "activated": invite_accepted.get(user_id, False),
                 "active": bool(active),
+                "manual": email.lower() in MANUAL_MEMBERS,
                 "balance": float(balance) if balance is not None else MEMBER_BUDGET,
                 "credit_balance": credits,
                 "allowance_used": eff["allowance_used"],