Vest platform: a client for Vest Markets, traded on a session the extension relays

Vest (next.vestmarkets.com) is a perps prop firm: index, metal and energy
perps on CME hours, plus stocks, FX and crypto. It joins as a fourth
platform, 'vest', on the DXtrade engine paths. Those are now keyed by
isNotionalPlatform() instead of === 'dxtrade': the firm's own symbols,
percent fees, notional sizing from volatility, and a scheduler lane of its
own.

- Login is relayed, not stored. Vest signs people in with Google through
  Privy and renews the session with a device key the browser won't export.
  Extension 0.17.0's vest-relay.js reads the token the Vest app renews for
  itself (~15 min). It renews nothing, so the tab is never logged out. The
  background script posts that token to POST /api/vest/session, which holds
  it in memory only. With no Vest tab open on a machine that trades Vest,
  the extension opens one.
- The firm's credential is the Vest login's wallet address. The dashboard's
  form offers the relayed wallet with one click.
- VestClient (lib/vest-class.ts), mapped from the web app's traffic and code
  since Vest publishes no API:
  - Reads the capital accounts, balances (free amount plus position
    collateral), positions and open orders with the user token.
  - Mints per-account tokens for orders and transactions.
  - Names accounts for their rules (V50K-E-D3-T10-34, V50K-F-D3-34,
    V25K-I-7) so account-type prefixes can match.
  - Takes Vest's own max-drawdown and daily-loss floors. dayStartBalance =
    floor + the type's limit, so the engine's room is never more than
    Vest's.
  - Uses each symbol's taker fee and margin rate from exchangeInfo, and
    hourly volatility over in-session hours only.
  - Places take-profit and stop as position legs, which Vest cancels as an
    OCO pair.
- Daily P&L and fund rows come from /v3/transactions by Vest's 20:00 ET
  day. A books check holds an account, naming the transaction types, when
  the balance and the transactions disagree.
- scripts/check-vest.mjs (in npm run check): Vest's day across DST, account
  names, parsing, volatility gaps, market hours, the session store.

Not yet run against Vest with a live session: the order and exit bodies
come from the app's code, and the transaction classification from its enum.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

extension/README.md

@@ -79,6 +79,31 @@ A new 2FA site needs its host in `host_permissions` (not the captcha
 `content_scripts` list), a Site link on its firm on the master, and its codes
 assigned on the master's Codes page.
 
+## Vest session relay
+
+Vest signs people in with Google (through Privy) in the browser and renews the
+session with a device key the browser will not export, so the dashboard cannot
+log in to Vest by itself. The extension relays the browser's session instead:
+
+```
+vest-relay.js (Vest tab, MAIN world)   keeps the access token the Vest app last renewed
+background.js  relayVestSession        lifts it every 10s, posts it when it changes
+dashboard      POST /api/vest/session  holds it in memory for the firm's Vest client
+```
+
+- The hook only reads the Vest app's own `/v3/auth/refresh` and `/register`
+  answers. It renews nothing and sends nothing; the session stays the app's,
+  so the bot never logs the tab out.
+- The token lives ~15 minutes and the app renews it by itself while the tab is
+  open. The tab is marked not auto-discardable, since a discarded tab stops
+  renewing.
+- When the dashboard has a Vest firm (its credential is the login's wallet)
+  and no Vest tab is open, the extension opens one in the background. The app
+  signs back in from its 30-day session. After that the person signs in again
+  in that tab.
+- This is the one place the extension reads a tab you are not looking at. It
+  only reads `next.vestmarkets.com` tabs, and only that one value.
+
 ## Notes
 
 - The extension never captures the dashboard's own pages — otherwise it would