refactor(compat): Prüfbausteine nach src/Compatibility, Matrix und ManifestCheck generisch

Requirement, Call, ConstantRequirement, Mirror, Problem, FeatureStatus, CompatibilityMatrix, Manifest, ManifestCheck sowie Fingerprints und LineDiff liegen jetzt im divi-freien Kern. Neu: GlobalRequirement, CompatibilityMatrix::fromProblems(), ManifestCheck-Option signatures, DiviManifestCheck::create() und DiviAreas. Divi-Verhalten unverändert.

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

src/Compatibility/ReleaseState.php

@@ -0,0 +1,15 @@
+<?php
+
+declare(strict_types=1);
+
+namespace LIT\MCP\Compatibility;
+
+defined('ABSPATH') || exit;
+
+/** Spec §5.2. */
+enum ReleaseState: string
+{
+    case Released = 'released';
+    case Untested = 'untested';
+    case Incompatible = 'incompatible';
+}