refactor: ChangeLog::recordPartial and column-size truncation

recordPartial() replaces the partial-log FollowUp blocks in content-create,
content-update and post-replace-with-copy; record() truncates ability,
object_type and object_id to their column sizes.

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

tests/Unit/Integrations/WordPress/Content/ContentUpdateAbilityTest.php

@@ -261,8 +261,8 @@ final class ContentUpdateAbilityTest extends TestCase
         $this->captureUpdates($updates);
         Functions\when('wp_revisions_enabled')->justReturn(false);
         $log = Mockery::mock(ChangeLog::class);
-        $log->expects('record')
-            ->with('lit/content-update', 'page', '5', Mockery::type('string'), 811, null, 'partial')
+        $log->expects('recordPartial')
+            ->with('lit/content-update', 'page', '5', Mockery::type('string'), 811)
             ->andReturn(12);
 
         $failure = $this->executeExpectingFailure($writer, $input, $log);