refactor: annotation presets (L5)

The 41 abilities return Annotations::read(), ::write(idempotent) or
::destructive(idempotent) instead of hand-written arrays (same arrays, same
key order).

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01At3V6SjwbMe6eMzVGW3Hs7

src/Abilities/Annotations.php

@@ -0,0 +1,31 @@
+<?php
+
+declare(strict_types=1);
+
+namespace LIT\MCP\Abilities;
+
+/**
+ * The MCP annotations of an ability (Ability::annotations()), in three presets. "readonly"
+ * drives the "nur lesen" group switch (ExposurePolicy::disabledByReadonly()) and, with
+ * "destructive", the Art column of the Tools tab (ruling S47).
+ */
+final class Annotations
+{
+    /** @return array{readonly: bool, destructive: bool, idempotent: bool} Reads only. */
+    public static function read(): array
+    {
+        return ['readonly' => true, 'destructive' => false, 'idempotent' => true];
+    }
+
+    /** @return array{readonly: bool, destructive: bool, idempotent: bool} Writes, removes or overwrites nothing. */
+    public static function write(bool $idempotent): array
+    {
+        return ['readonly' => false, 'destructive' => false, 'idempotent' => $idempotent];
+    }
+
+    /** @return array{readonly: bool, destructive: bool, idempotent: bool} Removes or overwrites something. */
+    public static function destructive(bool $idempotent): array
+    {
+        return ['readonly' => false, 'destructive' => true, 'idempotent' => $idempotent];
+    }
+}