chore(deps): bump rug from 1.26.1 to 1.28.1

[dependabot]

Bumps rug from 1.26.1 to 1.28.1.

Changelog

Sourced from rug's changelog.

Version 1.28.1 (2026-01-21)

• Bug fix: incorrect underflow when dividing Rational by Float (issue 85).

Version 1.28.0 (2025-08-21)

• The crate now requires rustc version 1.85.0 or later.
• The following methods were added to Float:
  • as_shl, as_shr
• The following methods were added to Complex:
  • as_shl, as_shr
• The experimental feature num-complex was added (issue 84).
• The experimental feature borsh was added (merge request 6).

Version 1.27.0 (2025-01-24)

• The [az crate], which is a dependency, is now re-exported ([issue 73]).
• The following methods were added to [Float][flo-1-27]:
  • [to_integer_in_place][flo-tiip-1-27], [to_integer_round_in_place][flo-tirip-1-27], [to_integer_exp_in_place][flo-tieip-1-27] ([issue 75])
  • [to_rational_in_place][flo-trip-1-27] ([issue 75])
  • [remainder_quo31][flo-rq-1-27], [remainder_quo31_mut][flo-rqm-1-27], [remainder_quo31_round][flo-rqr-1-27] ([issue 76])
  • [remainder_quo31_from][flo-rqf-1-27], [remainder_quo31_from_round][flo-rqfr-1-27]
  • [remainder_quo31_ref][flo-rqref-1-27]
  • [frexp][flo-f-1-27], [frexp_mut][flo-fm-1-27], [frexp_ref][flo-fr-1-27] ([issue 76])
• Bug fix: [Float][flo-1-27]::[to_f16][flo-tf16-1-27] and [Float][flo-1-27]::[to_f128][flo-tf128-1-27] were giving bad

... (truncated)

Commits

• f32bfef version 1.28.1
• e81c0c1 update copyright year
• e11f6d6 replace hardcoded constant in issue 85 test
• 635a32b mention issue 85 fix in relnotes
• ab17731 set style_edition = 2024
• a79f06a fix issue 85
• 7d09f6e test for issue 85
• e202c47 appease warning
• f07dc79 fix release notes links
• e4c3ddd version 1.28.0: fix doc typo
• Additional commits viewable in compare view

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