build(deps): bump nix from 0.28.0 to 0.31.2

[dependabot]

Bumps nix from 0.28.0 to 0.31.2.

Changelog

Sourced from nix's changelog.

[0.31.2] - 2026-02-28

Added

• Add WatchDescriptor::as_raw, to get libc id of WatchDescriptor. (#2718)
• Added process::pthread_getthreadid_np() on FreeBSD. (#2725)
• Added timerfd support on FreeBSD (#2728)

Fixed

• The libc requirement is now 0.2.181, rather than pinned to 0.2.180. (#2744)

[0.31.1] - 2026-01-23

Added

• termios: Add definition for IUCLC to supported platforms (#2702)
• termios: Add definition for XCASE for supported platforms (#2703)

[0.31.0] - 2026-01-22

Added

• Added the UDP GSO/GRO socket options and CMsgs on Android. This includes the following types:

  • UdpGsoSegment
  • UdpGroSegment
  • ControlMessage::UdpGsoSegments
  • ControlMessageOwned::UdpGroSegments

  (#2666)

• Define errno EWOULDBLOCK as an alias of EAGAIN to match the AIX libc definition. (#2692)

• Enable module ifaddrs on GNU Hurd (#2697)

• Add termios OutputFlags::OFILL for Linux, Android, Aix, Cygwin, Fuchsia, Haiku, GNU/Hurd, Nto, Redox, Illumos, Solaris and Apple OSes. (#2701)

• add sync() for cygwin (#2708)

Changed

... (truncated)

Commits

• bf1d0e9 chore: release v0.31.2
• 0dc1dd8 Unpin libc (#2744)
• dad24fb Allow timerfd use on FreeBSD (#2728)
• 6619d8d statfs: Fix definitions for s390x musl with libc 0.2.176 (#2678)
• 478594e Add api to get inner WatchDescriptor id, to work with c code. (#2718)
• 5507629 docs: minor fix in tcgetpgrp and tcsetpgrp doc comments (#2731)
• 9aea929 time: update comment in zero_init_timespec (#2730)
• b44fd1a FreeBSD: add pthread_getthreadid_np() (#2725)
• 06bb1be chore: release 0.31.1
• 49adb8d skip test::sys::test_af_alg_cipher on s390x,powerpc64le/Linux too (#2722)
• Additional commits viewable in compare view

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