docs: Divi guides shortform/placeholders, hints name the write tools; test: Divi write end-to-end; version 0.3.0

- Hints (PostPresenter::DIVI_NOTE, outline, catalog) and server instructions (tree_rev rule)
  name the Divi write tools; guides divi-shortform and divi-placeholders, additions to
  divi-structure, divi-attrs, overview (tool groups, 'nur lesen'), workflows, content-types.
- D7 wording and the S7 exception in readme, guides and spec 1.3/5.2; readme 0.3.0.
- ToolNamingTest: every referenced guide topic exists; overview lists exactly the topics.
- tests/Integration/divi-write-smoke.sh: all write tools via OAuth, editor without
  unfiltered_html with benign probes (S6), Divi's own save filters on the new fixture
  synthetic-divi-filters.html (S7); admin-render.php accepts the new wrap class.

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

tests/Unit/Guides/InstructionsBuilderTest.php

@@ -57,7 +57,9 @@ final class InstructionsBuilderTest extends TestCase
         $without = (new InstructionsBuilder(new IntegrationRegistry($core)))->build();
 
         self::assertStringContainsString('lit-divi-outline und lit-divi-design-system lesen', $with);
+        self::assertStringContainsString('tree_rev', $with);
         self::assertStringNotContainsString('lit-divi-outline und', $without);
+        self::assertStringNotContainsString('tree_rev', $without);
         self::assertLessThan(2000, strlen($with));
     }