CVE-2026-84364: Hono: Unbounded dot-notation nesting in `parseBody()` can cause memory exhaustion

When parseBody() expands dot-separated form field names into nested objects, it does not limit the nesting depth or the total number of objects created. A request body well within a normal size limit can therefore allocate an object graph far larger than the request itself, and concurrent requests can exhaust the heap and terminate the process.