chore: release v0.6.0

[github-actions]

🤖 New release

• flatzinc-serde: 0.5.1 -> 0.6.0 (⚠ API breaking changes)

⚠ flatzinc-serde breaking changes

--- failure enum_missing: pub enum removed or renamed ---

Description:
A publicly-visible enum cannot be imported by its prior path. A `pub use` may have been removed, or the enum itself may have been renamed or removed entirely.
        ref: https://doc.rust-lang.org/cargo/reference/semver.html#item-remove
       impl: https://github.com/obi1kenobi/cargo-semver-checks/tree/v0.48.0/src/lints/enum_missing.ron

Failed in:
  enum flatzinc_serde::AnnotationArgument, previously in file /tmp/.tmposOXoS/flatzinc-serde/src/lib.rs:169

--- failure enum_variant_added: enum variant added on exhaustive enum ---

Description:
A publicly-visible enum without #[non_exhaustive] has a new variant.
        ref: https://doc.rust-lang.org/cargo/reference/semver.html#enum-variant-new
       impl: https://github.com/obi1kenobi/cargo-semver-checks/tree/v0.48.0/src/lints/enum_variant_added.ron

Failed in:
  variant AnnotationLiteral:Literal in /tmp/.tmpRdB9M6/flatzinc-serde/src/lib.rs:198

--- failure enum_variant_missing: pub enum variant removed or renamed ---

Description:
A publicly-visible enum has at least one variant that is no longer available under its prior name. It may have been renamed or removed entirely.
        ref: https://doc.rust-lang.org/cargo/reference/semver.html#item-remove
       impl: https://github.com/obi1kenobi/cargo-semver-checks/tree/v0.48.0/src/lints/enum_variant_missing.ron

Failed in:
  variant AnnotationLiteral::Int, previously in file /tmp/.tmposOXoS/flatzinc-serde/src/lib.rs:199
  variant AnnotationLiteral::Float, previously in file /tmp/.tmposOXoS/flatzinc-serde/src/lib.rs:201
  variant AnnotationLiteral::Variable, previously in file /tmp/.tmposOXoS/flatzinc-serde/src/lib.rs:207
  variant AnnotationLiteral::Bool, previously in file /tmp/.tmposOXoS/flatzinc-serde/src/lib.rs:209
  variant AnnotationLiteral::IntSet, previously in file /tmp/.tmposOXoS/flatzinc-serde/src/lib.rs:215
  variant AnnotationLiteral::FloatSet, previously in file /tmp/.tmposOXoS/flatzinc-serde/src/lib.rs:222
  variant AnnotationLiteral::String, previously in file /tmp/.tmposOXoS/flatzinc-serde/src/lib.rs:228

Changelog

0.6.0 - 2026-08-03

Added

• [breaking] add opt-in interior mutability via a Ref type parameter
• use Arc for AnnotationLiteral

Other

• update dependencies

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This PR was generated with release-plz.