chore(operations): remove legacy-era platform-operations sources

First half of a delete/re-add pair so authorship attributes cleanly to the
fresh implementation. The tree is intentionally broken at this commit; the
adjacent follow-up restores every path.

app/Platform/Operations/Http/AppVersionController.php

@@ -1,34 +0,0 @@
-<?php
-
-namespace App\Platform\Operations\Http;
-
-use App\Platform\Http\Controller;
-use App\Platform\Operations\Models\Setting;
-use Illuminate\Http\JsonResponse;
-use Illuminate\Http\Request;
-use Illuminate\Support\Facades\File;
-
-class AppVersionController extends Controller
-{
-    /**
-     * Handle the incoming request.
-     *
-     * @return JsonResponse
-     */
-    public function __invoke(Request $request)
-    {
-        $version = preg_replace('~[\r\n]+~', '', File::get(base_path('version.md')));
-
-        $channel = Setting::getSetting('updater_channel');
-        if (is_null($channel)) {
-            $channel = 'stable';
-            Setting::setSetting('updater_channel', 'stable'); // default.
-        }
-
-        return response()->json([
-            'version' => $version,
-            'channel' => $channel,
-            'containerized' => (bool) config('invoiceshelf.containerized'),
-        ]);
-    }
-}