chore(deps): bump rust-i18n from 3.1.5 to 4.2.1

[dependabot]

Bumps rust-i18n from 3.1.5 to 4.2.1.

Release notes

Sourced from rust-i18n's releases.

v4.2.1

What's Changed

• Use serde-saphyr for YAML parsing by @​huacnlee with @​Copilot in longbridge/rust-i18n#144

Full Changelog: longbridge/rust-i18n@v4.2.0...v4.2.1

v4.2.0

What's Changed

• Add extend! macro to extend crate's translations by @​huacnlee in longbridge/rust-i18n#143

Full Changelog: longbridge/rust-i18n@v4.1.0...v4.2.0

v4.1.0

What's Changed

• fix: enable codegen feature for rust-i18n-support in dev-dependencies by @​sunli829 in longbridge/rust-i18n#141

Full Changelog: longbridge/rust-i18n@v4.0.0...v4.1.0

v4.0.0

What's Changed

Breaking Changes

• Backend trait signature changed to use Cow<'_, str> — available_locales() now returns Vec<Cow<'_, str>> instead of Vec<&str>, and translate() now returns Option<Cow<'_, str>> instead of Option<&str>. Custom Backend implementations must be updated accordingly. (#114)
• SimpleBackend::add_translations() signature changed — Now takes Cow<'static, str> for locale and HashMap<Cow<'static, str>, Cow<'static, str>> for data, instead of &str and &HashMap<&str, &str>. (#133)
• New required method messages_for_locale on Backend trait — Returns all translation messages for a given locale as Option<Vec<(Cow<'_, str>, Cow<'_, str>)>>.
• Removed once_cell dependency — Replaced with std::sync::LazyLock from the standard library. The re-export rust_i18n::once_cell is no longer available. This raises the minimum supported Rust version (MSRV) to 1.80.0. (#131)

Performance Improvements

• Dramatically reduced allocations in the i18n! macro expansion — Previously, the macro generated one HashMap per translation pair; now it generates one HashMap per locale. For large projects, this reduces HashMap creation from thousands to just a handful (e.g., 14,000 → 32). This also fixes stack overflow crashes on Windows for projects with many translations. (#133)
• Eliminated unnecessary String allocations — By using Cow<'static, str> throughout, static translation strings are no longer cloned into heap-allocated Strings. (#114, #133)

New Features

• messages_for_locale() method on Backend — Retrieve all translation key-value pairs for a specific locale, useful for inspection and debugging.
• try_load_locales() function — A fallible alternative to load_locales() in rust-i18n-support that returns Result instead of panicking, with detailed error messages for file lookup, parsing, and I/O failures. (#127)
• Improved error messages — Parsing failures now include the specific error reason instead of a generic panic message. (#116)

Internal / Maintenance

• Replaced once_cell::sync::Lazy with std::sync::LazyLock (#131)
• Added Cargo.lock to version control (#120)
• Improved CI workflow with concurrency groups and branch filtering
• Added release workflow
• Bumped slab from 0.4.10 to 0.4.11 (#122)

... (truncated)

Commits

• 933fb3f Version 4.2.1
• cc7e328 Use serde-saphyr for YAML parsing (#144)
• 0ac6f61 Version 4.2.0
• a8aadf7 Add extend! macro to extend crate's translations (#143)
• bd315ec Update versions in README (#142)
• 97cf091 fix: enable codegen feature for rust-i18n-support in dev-dependencies (#141)
• d2aaa49 docs: Add user cases. (#132)
• a931914 Version 4.0.0
• 410adde Reduce allocations create unnecessary HashMaps and Strings (#133)
• 94a91a7 docs: Update user cases. (#134)
• Additional commits viewable in compare view

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[Tuntii]

Held on purpose during repo hygiene (2026-09-05). This is a major/breaking bump, not a drive-by merge. We'll take it in a dedicated PR after main is green again (#266). Please don't squash-merge this as-is.

[Tuntii]

Superseded by #270 (single lockfile PR for all remaining majors). Closing this Dependabot bump.

[dependabot]

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