fix: name the WordPress revision screen for library and layout revisions (audit L3)

lit/revision-restore takes only content types, so a write to a library entry
or a Theme Builder layout now answers with restore_url (wp-admin
revision.php for its revision_id), also per page in lit/divi-replace-text.
The guides and readme no longer present lit/revision-restore as the way back
for these types.

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

tests/Unit/Integrations/Divi/Pages/DiviWriterThemeBuilderTest.php

@@ -86,6 +86,8 @@ final class DiviWriterThemeBuilderTest extends TestCase
         self::assertTrue($result['ok']);
         self::assertCount(1, $this->saved);
         self::assertSame(1066, $result['templates'][0]['id']);
+        // Audit L3: lit/revision-restore does not take Theme Builder layouts – the WordPress revision screen does.
+        self::assertSame('https://kunde.test/wp-admin/revision.php?revision=811', $result['restore_url']);
     }
 
     public function testLayoutOfADisabledTemplateSavesAtOnce(): void