feat: Divi release status, store, resolver and gate

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

src/Integrations/Divi/Release/DiviLocked.php

@@ -0,0 +1,41 @@
+<?php
+
+declare(strict_types=1);
+
+namespace LIT\MCP\Integrations\Divi\Release;
+
+use RuntimeException;
+use Throwable;
+use WP_Error;
+
+defined('ABSPATH') || exit;
+
+/** A write refused because the installed Divi is not released (spec §5.5); AbilityRegistrar returns toError(). */
+final class DiviLocked extends RuntimeException
+{
+    public function __construct(public readonly ReleaseStatus $status)
+    {
+        parent::__construct(sprintf(
+            '%s is %s for LIT MCP – write refused',
+            $status->versionLabel(),
+            $status->state->value
+        ));
+    }
+
+    public function toError(): WP_Error
+    {
+        return $this->status->refusal();
+    }
+
+    /** The lock anywhere in $e's chain of previous exceptions (callers wrap failures in WriteFailed). */
+    public static function in(Throwable $e): ?self
+    {
+        for ($cause = $e; $cause !== null; $cause = $cause->getPrevious()) {
+            if ($cause instanceof self) {
+                return $cause;
+            }
+        }
+
+        return null;
+    }
+}