feat: chain:stop command + DNS update activity logging

chain:stop sends SIGTERM and waits for graceful shutdown.
DNS updateRecords now logs 'dns_updated' activity with ticket_id
and records. Claim approve/reject also logged in previous commit.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

app/Mod/Chain/Boot.php

@@ -37,6 +37,7 @@ class Boot
     public function onConsole(ConsoleBooting $event): void
     {
         $event->command(Commands\ChainStart::class);
+        $event->command(Commands\ChainStop::class);
         $event->command(Commands\ChainStatus::class);
     }
 }

app/Mod/Chain/Commands/ChainStop.php

@@ -0,0 +1,58 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Mod\Chain\Commands;
+
+use Illuminate\Console\Command;
+
+/**
+ * Gracefully stop chain daemon and wallet.
+ *
+ *   php artisan chain:stop
+ */
+class ChainStop extends Command
+{
+    protected $signature = 'chain:stop';
+
+    protected $description = 'Stop testnet chain daemon and wallet';
+
+    public function handle(): int
+    {
+        $this->stopProcess('lethean-wallet-cli', 'Wallet');
+        $this->stopProcess('lethean-testnet-chain-node', 'Daemon');
+
+        return self::SUCCESS;
+    }
+
+    private function stopProcess(string $name, string $label): void
+    {
+        // Safe: escapeshellarg prevents injection, process names are hardcoded constants
+        exec("pgrep -f " . escapeshellarg($name), $pids); // @codeCoverageIgnore
+
+        if (empty($pids)) {
+            $this->info("{$label}: not running.");
+
+            return;
+        }
+
+        foreach ($pids as $pid) {
+            posix_kill((int) $pid, SIGTERM);
+        }
+
+        $this->info("{$label}: SIGTERM sent to " . count($pids) . " process(es).");
+
+        // Wait up to 10s for graceful shutdown
+        for ($i = 0; $i < 10; $i++) {
+            exec("pgrep -f " . escapeshellarg($name), $check); // @codeCoverageIgnore
+            if (empty($check)) {
+                $this->info("{$label}: stopped.");
+
+                return;
+            }
+            sleep(1);
+        }
+
+        $this->warn("{$label}: still running after 10s.");
+    }
+}

app/Mod/Names/Controllers/NamesController.php

@@ -282,6 +282,7 @@ class NamesController extends Controller
         if (isset($result['tx_id'])) {
             Cache::put($editLock, true, 300);
             $ticket = Models\DnsTicket::open($name, $records, $result['tx_id'], $address, $comment);
+            Models\NameActivity::log($name, 'dns_updated', ['ticket_id' => $ticket->ticket_id, 'records' => $records], request()?->ip());
 
             return response()->json([
                 'name' => $name,