Vest: record every trade, the bot's and outside ones, and list them

Vest's position history (GET /v3/positions) gives each position's size,
open and close price, P&L, fees, funding and why it closed. The client
reads it hourly and a minute after a position closes (or a flat balance
moves) into a new trades table, and stores open positions as they
appear. Vest can't tell an API order from a click, so the bot marks its
own opens and closes as it sends them; an unmarked trade since marking
began was someone else's.

The dashboard's Vest firm row gets a Trades button listing every trade
on its accounts with who opened it and how it closed; the account page
shows its own.

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

types.ts

@@ -176,3 +176,30 @@ export interface FirmState {
     connected: boolean;
     accounts: AccountState[];
 }
+
+/** One recorded position (GET /api/trades) — Vest's position history plus
+ *  what this instance did itself. */
+export interface TradeView {
+    positionId: string;
+    accountId: number;
+    accountName: string;
+    symbol: string;
+    side: 'long' | 'short';
+    quantity: number;
+    openPrice: number | null;
+    closePrice: number | null;
+    /** Realized P&L before fees and funding. */
+    pnl: number | null;
+    fee: number | null;
+    funding: number | null;
+    /** pnl − fee + funding; null while open (or unknown). */
+    net: number | null;
+    openedAt: number;
+    closedAt: number | null;
+    /** null: opened before this instance began marking its own trades. */
+    openedBy: 'bot' | 'outside' | null;
+    /** null while open; else 'bot', 'outside' (closed by hand or another
+     *  tool), or the platform's own reason (stop_loss, take_profit,
+     *  liquidation, …; user_requested from before marking began). */
+    closedBy: string | null;
+}