Backups to master, replacement-VPS restore, broker proxy, multi-instance

Four features:

- Backup: lib/backup-sync.ts pushes the full settings table and firm
  credentials (the deliberate exception to "credentials never leave the
  machine") to the master's bearer-gated /api/instances/backup — every
  5 minutes when the content hash changed, within seconds of a settings
  or credential edit, and on the new backup-now command. Enabled by the
  master_backup_token setting.

- Restore: a dead VPS's replacement pulls the backup and adopts its
  uuid/name, so roster, payouts and card links carry on. Pre-boot via
  seed-settings.js --restore-from (setup-linux.sh prompts for it) or
  the Settings page's restore picker (lib/backup-restore.ts). Stop the
  old machine first; the master 409s a live-name rename.

- Proxy: the proxy_url setting routes BROKER traffic only — TopstepX
  REST + SignalR hub, Tradovate REST + websocket, Yahoo quotes — via
  lib/outbound-proxy.ts (axios agents, undici dispatcher, ws agent).
  The master link, reporter, catalog and backup push stay direct, so a
  dead proxy cannot take down the control channel. Restart to apply.

- Multi-instance: AUTOFIRMER_DB moves the SQLite file so one checkout
  runs N instances; scripts/instances.json (per-device, gitignored)
  drives start-all/update-check, and add-instance.sh / remove-instance.sh
  manage the extra PM2 processes. Absent registry = single-instance
  behavior, unchanged. Instance 1 keeps port 3000 for the clicker and
  extension.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

lib/tradovate-class.ts

@@ -6,6 +6,7 @@ import { computeSec, randomUUIDV4 } from './tradovate-helpers';
 import { POINT_VALUES } from './trading-logic';
 import { getCachedContract, resolveContracts } from './contract-resolver';
 import { saveDailyPnL, loadDailyPnL, saveAccountMeta, loadAccountMeta, saveFundTransactions, loadFundTransactions } from './db';
+import { brokerWebSocket } from './outbound-proxy';
 
 /**
  * Entity types Tradovate sends over the user-sync socket. Keep this as the
@@ -147,7 +148,9 @@ export class TradovateClient {
             this.syncComplete = false;
 
             const randomnumber = Math.random().toString(36).substring(2, 15);
-            this.ws = new WebSocket(`wss://demo.tradovateapi.com/v1/websocket?r=${randomnumber}`);
+            // Broker endpoint — dialled through the operator's proxy when one
+            // is configured (lib/outbound-proxy.ts).
+            this.ws = brokerWebSocket(`wss://demo.tradovateapi.com/v1/websocket?r=${randomnumber}`);
 
             this.ws.onopen = () => {
                 console.log('Connected to websocket');