feat: tick planner, delivery job, scheduler and purge

Also: test uses disabled channels instead of deleting them (FK cascade); ChannelRegistry no longer final so tests can extend it (controller ruling).

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01BCrwHHnGCB5XH968Nxokqw

core/app/Console/Commands/TickCommand.php

@@ -0,0 +1,20 @@
+<?php
+
+namespace App\Console\Commands;
+
+use App\Delivery\Tick;
+use Illuminate\Console\Command;
+
+class TickCommand extends Command
+{
+    protected $signature = 'hado:tick';
+
+    protected $description = 'Один тик: переходы состояний и доставка напоминаний в открытые окна';
+
+    public function handle(Tick $tick): int
+    {
+        $tick->run();
+
+        return self::SUCCESS;
+    }
+}