feat: restore legacy named playlist workflows

tests/Web/legacy-foreign-index-candle-workflow.test.cjs

@@ -209,6 +209,25 @@ test("legacy signature round-trips only the exact verified entry", () => {
   }
 });
 
+test("enabled replacement preserves the branded foreign-index proof immutably", () => {
+  const storedRaw = raw("S&P500", "20일", 6, true);
+  const pending = workflow.classify(storedRaw, {
+    id: "foreign_toggle", fadeDuration: 6
+  });
+  const normalized = workflow.normalizeResponse(response("load_toggle", [pending]),
+    "load_toggle", [pending]);
+  const entry = workflow.materialize(pending, normalized.rows[0]);
+  const replacement = workflow.withEnabled(entry, false);
+
+  assert.notEqual(replacement, entry);
+  assert.equal(Object.isFrozen(replacement), true);
+  assert.equal(entry.enabled, true);
+  assert.equal(replacement.enabled, false);
+  assert.equal(workflow.isMaterializedEntry(replacement), true);
+  assert.equal(workflow.matchesRaw(replacement, { ...storedRaw, enabled: false }), true);
+  assert.equal(workflow.withEnabled({ ...entry }, false), null);
+});
+
 test("bridge errors are request-bound and never retryable", () => {
   const error = {
     requestId: "load_error",