fix(reference): preserve module syntax and loader request identity

src/domain/javascript/javascriptModuleSpecifier.ts

@@ -1,6 +1,27 @@
+import { err, ok, type Result } from "../result.js";
+
 /** Relative module syntax differs from an arbitrary dot-prefixed filename. */
 export const isRelativeJavaScriptModuleSpecifier = (value: string): boolean =>
   value === "." ||
   value === ".." ||
   value.startsWith("./") ||
   value.startsWith("../");
+
+/** Node file-module URL paths decode once and reject encoded separators. */
+export const decodeJavaScriptModuleUrlPath = (
+  value: string,
+): Result<string, string> => {
+  if (/%(?:2f|5c)/iu.test(value))
+    return err(
+      "ES module URL paths cannot contain percent-encoded slash or backslash bytes.",
+    );
+  try {
+    const decoded = decodeURIComponent(value);
+    return decoded.includes("\0")
+      ? err("The decoded module URL path contains NUL.")
+      : ok(decoded);
+  } catch (cause: unknown) {
+    if (!(cause instanceof URIError)) throw cause;
+    return err("The module URL path contains malformed percent encoding.");
+  }
+};