fix(javascript): preserve case-sensitive Unicode seed identity

Use NFC for case-sensitive feature seeds while preserving the existing explicit insensitive compatibility fold.

Validation: exact/substring/absent controls, fresh public CLI/MCP workflows and complete exact-head CI passed. Hosted CLI-worker failure and unchanged rerun results remain recorded in the PR.

Fixes #3314.

src/domain/javascript/javascriptFeatureSeed.ts

@@ -273,7 +273,7 @@ const propertyFields = (
 };
 
 const normalized = (value: string, caseSensitive: boolean): string => {
-  const normalizedValue = value.normalize("NFKC");
+  const normalizedValue = value.normalize(caseSensitive ? "NFC" : "NFKC");
   return caseSensitive
     ? normalizedValue
     : normalizedValue.toLocaleLowerCase("en-US");