curl --request GET \
  --url https://api.simmer.markets/api/sdk/portfolio

{
  "balance_usdc": 123,
  "sim_balance": 123,
  "sim_pnl": 123,
  "total_exposure": 123,
  "positions_count": 123,
  "redeemable_count": 123,
  "pnl_24h": 123,
  "pnl_total": 123,
  "concentration": {
    "top_market_pct": 123,
    "top_3_markets_pct": 123
  },
  "by_source": {}
}