nexusformat/definitions: NXDL 2026.01

What's Changed Recategorise some application definitions for #1602 by @PeterC-DLS in https://github.com/nexusformat/definitions/pull/1603 datetime.UTC introduced in python 3.11 by @woutdenolf in https://github.com/nexusformat/definitions/pull/1593 Expose deprecated attributes in docs for #1605 by @PeterC-DLS in https://github.com/nexusformat/definitions/pull/1607 Fix CI broken by updated tooling by @PeterC-DLS in https://github.com/nexusformat/definitions/pull/1616 Ensure any reference to inherited nodes match tag type by @PeterC-DLS in https://github.com/nexusformat/definitions/pull/1608 Deprecate thumbnail's type attribute for #1605 by @PeterC-DLS in https://github.com/nexusformat/definitions/pull/1606 Remove specification of one year curation requirement for contributions by @phyy-nx in https://github.com/nexusformat/definitions/pull/1599 Update NXparameter documentation by @rayosborn in https://github.com/nexusformat/definitions/pull/1560 Fairmat 2025: adding SPM to contributed definitions by @mkuehbach in https://github.com/nexusformat/definitions/pull/1589 Update copyright date 2026 by @PeterC-DLS in https://github.com/nexusformat/definitions/pull/1617 Release notes: Wiki v2026.01 Summary: CHANGES Full Changelog: https://github.com/nexusformat/definitions/compare/v2025.11...v2026.01