Search: Remove suggest multi-field from ai_questions mapping

Keep the suggest completion field only on ai_autocomplete_questions.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: reakaleek

src/Elastic.Documentation/Search/DocumentationMappingConfig.cs

@@ -73,8 +73,7 @@ internal static MappingsBuilder<DocumentationDocument> ConfigureCommonMappings(M
 			.MultiField("completion", mf => mf.SearchAsYouType()
 				.Analyzer("synonyms_fixed_analyzer")
 				.SearchAnalyzer("synonyms_analyzer")
-				.IndexOptions("offsets"))
-			.MultiField("suggest", mf => mf.Completion()))
+				.IndexOptions("offsets")))
 		.AddField("ai_autocomplete_questions", f => f.Text()
 			.Analyzer("synonyms_fixed_analyzer")
 			.SearchAnalyzer("synonyms_analyzer")