feat(canvas): let admins drag server zones on the servers and dashboard canvases

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

database/migrations/2026_10_23_200902_add_canvas_position_to_servers_table.php

@@ -0,0 +1,22 @@
+<?php
+
+use Illuminate\Database\Migrations\Migration;
+use Illuminate\Database\Schema\Blueprint;
+use Illuminate\Support\Facades\Schema;
+
+return new class extends Migration
+{
+    public function up(): void
+    {
+        Schema::table('servers', function (Blueprint $table) {
+            $table->json('canvas_position')->nullable();
+        });
+    }
+
+    public function down(): void
+    {
+        Schema::table('servers', function (Blueprint $table) {
+            $table->dropColumn('canvas_position');
+        });
+    }
+};