feat(references): cap formatted references at 30 with truncation notice

Prevents flooding the context window when a common symbol has hundreds
of references. Shows the first 30 and appends a count of the remainder.

index.ts

@@ -68,13 +68,20 @@ function formatReferences(result: unknown): string {
   if (!result || !Array.isArray(result)) return "(no references found)";
   if (result.length === 0) return "(no references found)";
 
-  return result
+  const limit = 30;
+  const shown = result.slice(0, limit);
+  const formatted = shown
     .map((loc: any, i: number) => {
       const file = uriToPath(loc.uri);
       const range = loc.range;
       return `${i + 1}. ${file} (${range.start.line + 1}:${range.start.character + 1})`;
     })
     .join("\n");
+
+  if (result.length > limit) {
+    return `${formatted}\n\n... and ${result.length - limit} more references (showing first ${limit})`;
+  }
+  return formatted;
 }
 
 // Format Completions - Turn completion items into readable text.