refactor: consolidate boundary semantics and prune redundant tests

Share parser modes and collision-free composite keys, enforce architecture guards, and consolidate redundant unit assertions into filesystem, CLI, MCP, and producer-backed workflows. Preserve concurrent upstream boundary fixes and exclude legacy Objective-C class-name bookkeeping labels.

Validation: source/composition suites (3358 passing), focused canonical digest and MCP checks, typecheck/lint, Knip, formatting, architecture guards, and real Foundation archive and Apple legacy simulator CLI/MCP verification. No real Hopper, Ghidra, or IDA verification claim.

src/domain/javascript/javascriptSemanticTraversal.ts

@@ -50,7 +50,11 @@ interface TraversalFrame {
   nextIndex: number;
 }
 
-/** Return child Babel nodes in visitor-key order. */
+/**
+ * Child Babel nodes in `VISITOR_KEYS` order. Single owner for AST child
+ * expansion; bespoke `Object.values` / duplicated `childNodes` walkers must
+ * not be reintroduced (they diverge on loc/comment fields and ordering).
+ */
 export const childNodes = (node: t.Node): t.Node[] => {
   const keys = t.VISITOR_KEYS[node.type];
   if (keys === undefined) return [];