* feat(rust-toolchain): Implement `rust-toolchain` manager
* feat(rust-toolchain): Add support for legacy filename
* feat(rust-toolchain): Add support for legacy file format
* refactor(rust-toolchain): Reject empty `channel` strings at parse stage
* tests(rust-toolchain): Cover valid TOML missing `[toolchain]` or `channel`
* refactor(rust-toolchain): Log legacy format fallback at `trace` level
* refactor(rust-toolchain): Reject empty and multi-line legacy files explicitly
* tests(rust-toolchain): Cover unparseable channel value
* tests(rust-toolchain): Use `codeBlock` for multi-line fixtures
* docs(rust-toolchain): Scope pin example to `rust-toolchain` manager
Co-authored-by: Sergei Zharinov <1239644+zharinov@users.noreply.github.com>
* tests(rust-toolchain): Use `codeBlock` for schema fixtures too
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Co-authored-by: Sergei Zharinov <1239644+zharinov@users.noreply.github.com>
Tobias Bieniek