public CompletionItem getBodySnippet() {
            return getBodySnippet(false);
        }
Turns this keyword body into a snippet of itself, with the keyword { ...items } syntax.
@param hasAdditionalSpec specifies if there should be an identifier after the keyword, i.e. match field_name: ...
integration/schema-language-server/language-server/src/main/java/ai/vespa/schemals/lsp/schema/completion/provider/FixedKeywordBodies.java