Eng-council sweep: export hygiene, dead code, helper dedup, declare vega-expression

src/core/json-format.ts

@@ -12,7 +12,7 @@
 import stringify from 'json-stringify-pretty-compact';
 
 /** Width budget before an array/object wraps onto multiple lines. */
-export const DEFAULT_MAX_LINE = 80;
+const DEFAULT_MAX_LINE = 80;
 
 /** Default indent (spaces) — matches the editor's default tab size (spec §07). */
 const DEFAULT_INDENT = 2;