FS_REGISTER_CFG(fs_config_t fs_config) = {
    .callback = fs_event_handler,
    .num_pages = 20,  // 4 pages * 4KB = 16KB
    .priority = 0xFF,
    .p_start_addr = (uint32_t*)0x60000,
    .p_end_addr = (uint32_t*)0x74000  // Exclusive: ends at 0x78FFF
};