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/clients.ts

@@ -6,6 +6,8 @@ import { getTradableFirms, startCatalogSync } from './firm-catalog';
 import { resolveFirmAssignments } from './account-type-resolver';
 import { resolveContracts } from './contract-resolver';
 import { startReporter, sendReport } from './reporter';
+import { startBackupSync } from './backup-sync';
+import { applyBrokerProxy } from './outbound-proxy';
 import { startMasterLink } from './master-link';
 import { resumeSchedulerIfPersisted } from './auto-trade';
 
@@ -128,6 +130,10 @@ export function getClients(): Map<string, PlatformClient> {
     if (!g.__tradovateClientsInitialized) {
         g.__tradovateClientsInitialized = true;
         try {
+            // Before anything dials out: put the operator's proxy (if any)
+            // under the broker clients. Master traffic stays direct by design.
+            applyBrokerProxy();
+
             // Pull the catalog before anything else — without it there are no
             // firms to start clients for. Subsequent changes re-reconcile and
             // re-resolve, so a new account type picks up accounts that were
@@ -155,6 +161,10 @@ export function getClients(): Map<string, PlatformClient> {
             // Start master dashboard reporter
             startReporter();
 
+            // Push settings+credentials backups to the master, so a dead VPS
+            // can be replaced and this identity adopted.
+            startBackupSync();
+
             // ...and the socket it prefers to report over, which is also how
             // the master triggers trades and AutoBuyer runs here.
             startMasterLink(() => { void sendReport(); });