Update darling requirement from 0.21 to 0.22

[dependabot]

Updates the requirements on darling to permit the latest version.

Release notes

Sourced from darling's releases.

v0.22.0

• BREAKING: Remove fnv dependency, as runtime performance gain does not justify additional dependency. This was exposed to users of darling::usage, so it may be breaking for them #373
• Add #[darling(default = || expr(val))] support, allowing a closure where a path was previously required #380
• Preserve span information for paths given to darling::util::Callable as literal strings
• Fix some documentation typos

Changelog

Sourced from darling's changelog.

v0.22.0 (December 2, 2025)

• BREAKING: Remove fnv dependency, as runtime performance gain does not justify additional dependency. This was exposed to users of darling::usage, so it may be breaking for them #373
• Add #[darling(default = || expr(val))] support, allowing a closure where a path was previously required #380
• Preserve span information for paths given to darling::util::Callable as literal strings
• Fix some documentation typos

v0.21.3 (August 22, 2025)

• Fix: Forward Override::<T>::from_expr to T::from_expr #371

v0.21.2 (August 14, 2025)

• Add #[darling(from_expr = ...)] when deriving FromMeta to support overriding the key-value form #369
• Keep parsing the body and type params even if there are errors from parsing attributes. #7
• Support #[darling(with = ...)] on the generics field when deriving FromDeriveInput.
• Return an error, rather than panicking, when doing shape validation on a union. #365

v0.21.1 (August 4, 2025)

• Track all alternate field names, and show them in error message if there aren't too many. #325
• Track all alternate values for enum variants, and show them in error messages if there aren't too many. #362

v0.21.0 (July 10, 2025)

• Potentially breaking: Emit error when an attribute path is present in both attributes and forward_attrs. #336
• Support parsing attributes which contain keywords #238
• Add SpannedValue::into_inner #342
• Add #[darling(derive_syn_parse)] to also impl syn::parse::Parse when deriving FromMeta #285
• Make impl FromMeta for syn::TypePath support both quote-wrapped and bare values #351
• Add util::PreservedStrExpr #346
• Impl UsesTypeParams and UsesLifetimes for WithOriginal #215
• Update error message emitted by <() as FromMeta>::from_list to allow use of () as a #[darling(flatten)] target #353

v0.20.11 (March 28, 2025)

• Support #[darling(with = ...)] on the data field when deriving FromDeriveInput. This allows the use of simpler receiver types, such as a Vec of enum variants.
• Bump version of proc-macro2 to 1.0.86.
• Accept closures for #[darling(with = ...)] on fields in FromDeriveInput, FromMeta, FromField, etc. #309
• Add darling::util::Callable to accept a path or closure as a meta-item expression
• Add #[darling(from_word = ...)] and #[darling(from_none = ...)] to control shorthand and fallback behaviors for structs and enums deriving FromMeta #320
• Add FromMeta impl for syn::ExprRange #329

v0.20.10 (July 9, 2024)

• Add #[allow(clippy::manual_unwrap_or_default)] to all generated impls to avoid causing clippy fails in crates using darling #296
• Properly initialize attrs magic field in derived FromAttributes impls #297

... (truncated)

Commits

• 3947278 Bump version to 0.22.0
• cd33f9b chore: fix some minor issues in the comments
• 2ca795b docs: fix minor typo in top-level doc comment ('its' → 'it’s')
• 878b5ba Lock min version of proc-macro2
• 7536387 Lock quote version
• 775bf91 Set rust-version for all crates consistently
• 3b0cbb7 Update compile-fail tests for default expr
• d711a69 Docs: add custom default usage to landing page
• 39dda63 Add support for closure as argument to default
• 59a95fd Fix: Preserve span for Callable path as LitStr
• Additional commits viewable in compare view

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