Upgrade and move USDC

POST /api/me/vault/upgrade
X-Api-Key: ps_live_<keyId>_<secret>   # needs `vault:migrate` or `vault:write` scope
Content-Type: application/json

{}

const sleep = (ms: number) => new Promise(r => setTimeout(r, ms));
// Retry only what the table marks as retryable; give up after a few attempts.
for (let attempt = 0; attempt < 10; attempt++) {
  const r = await fetch(`${BASE}/api/me/vault/upgrade`, { method: 'POST', headers: auth, body: '{}' });
  const body = await r.json();
  if (r.status === 200 && Number(body.generation) === 2) break;               // active
  const code = body?.error?.code;
  const retryable = r.status === 202 || r.status >= 500 || code === 'vault_deploy_failed';
  if (!retryable) throw new Error(`upgrade refused: ${r.status} ${code}`);
  await sleep((Number(body?.error?.retryAfterSec) || 5) * 1000);             // after 202: deploy still running
}

const r = await fetch(`${BASE}/api/me/vault/upgrade/transfer`, {
  method: 'POST', headers: auth, body: JSON.stringify(amount ? { amount } : {}),
});
const { transfer: t } = await r.json();
if (r.status === 200 && amount && parseUnits(t.amount, 6) !== parseUnits(amount, 6)) {
  throw new Error(`open move ${t.id} is for ${t.amount}`);   // wait for it to end, then create a new one
}
const srs = t.signRequests;
if (srs) {
  const { withdraw: w, permit: p } = srs;
  if (w.domain.verifyingContract.toLowerCase() !== gen1Vault.toLowerCase()) throw new Error('not my generation-1 vault');
  if (w.message.token.toLowerCase() !== contracts.usdc.toLowerCase()) throw new Error('not USDC');
  if (BigInt(w.message.amount) !== parseUnits(t.amount, 6)) throw new Error('amount mismatch');

  const userSig = await eoa.signTypedData(
    { ...w.domain, chainId: Number(w.domain.chainId) },
    { WithdrawERC20: w.types.WithdrawERC20 },
    w.message,
  );

  let permitSig: string | undefined;
  if (p) {
    permitSig = await eoa.signTypedData(
      { ...p.domain, chainId: Number(p.domain.chainId) },
      { Permit: p.types.Permit },
      p.message,
    );
  }

  await fetch(`${BASE}/api/me/vault/upgrade/transfer/${t.id}/signature`, {
    method: 'POST', headers: auth, body: JSON.stringify({ userSig, permitSig }),
  });
}
// poll GET /api/me/vault/upgrade/transfer/{id} until a terminal status