refactor: DiviTextSearch out of the replace-text ability (M2)

The SQL prefilter and the per-page hit computation move to DiviTextSearch;
DiviPageLoader::loadWritable serves DiviWriter::page and the dry run;
PostStatuses::NOT_CONTENT replaces the duplicated status list (same set,
order in the SQL list only). The private log() wrapper is inlined.

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

src/Integrations/Divi/Pages/DiviWriter.php

@@ -45,16 +45,11 @@ class DiviWriter
      */
     public function page(array $input): DiviPage|WP_Error
     {
-        $page = $this->loader->load($input['post_id'] ?? null, true);
+        $page = $this->loader->loadWritable($input['post_id'] ?? null);
         if ($page instanceof WP_Error) {
             return $page;
         }
 
-        $problem = $this->loader->writable($page);
-        if ($problem !== null) {
-            return $problem;
-        }
-
         if (! is_string($input['tree_rev'] ?? null) || $input['tree_rev'] !== $page->treeRev()) {
             return Errors::revMismatch(
                 'Die Divi-Seite wurde seit dem letzten Lesen geändert (tree_rev passt nicht); nichts wurde '