feat: Divi read tools accept library entries (library access, E1/E3)

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

src/Abilities/ExposurePolicy.php

@@ -181,6 +181,15 @@ final class ExposurePolicy
         return isset($this->readonlyGroups[$group]);
     }
 
+    /**
+     * Whether $group is switched on at all: not disabled as a whole ("nur lesen" still reads). The
+     * group "Divi-Bibliothek" disabled hides library entries from the Divi read tools (ruling P9).
+     */
+    public function groupEnabled(string $group): bool
+    {
+        return $this->groupMode($group) !== self::DISABLED;
+    }
+
     public function defaultMode(Ability $ability): string
     {
         return $ability->isDirect() ? self::DIRECT : self::INDIRECT;