Report the running build's version to the master

The version is the checkout's HEAD commit (short hash + commit time),
read once at startup — updates arrive as `git pull`, so there is no
release number to bump. It rides on the socket hello, socket reports,
and the HTTP report fallback; the field is optional in the protocol so
older masters ignore it.

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

lib/master-link.ts

@@ -20,6 +20,7 @@ import { runTrade, startScheduler, stopScheduler, getSchedulerStatus } from './a
 import { FIRMS, automationKey } from './automations';
 import { POINT_VALUES } from './trading-logic';
 import { queueRun } from './queue-run';
+import { getBuildVersion } from './version';
 import type {
     Command,
     InstanceCapabilities,
@@ -161,6 +162,7 @@ export function pushReport(firms: unknown[], scheduler: unknown): boolean {
         firms: firms as never,
         scheduler: scheduler as never,
         capabilities: collectCapabilities(),
+        version: getBuildVersion() ?? undefined,
     });
 }
 
@@ -226,6 +228,7 @@ function connect() {
             instance,
             id: instanceId || undefined,
             capabilities: collectCapabilities(),
+            version: getBuildVersion() ?? undefined,
         } satisfies InstanceMessage));
     });