chore(deps): update rust to v1.91.1 (#565)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| [rust](https://redirect.github.com/rust-lang/rust) | patch | `1.91.0`
-> `1.91.1` |

---

### Release Notes

<details>
<summary>rust-lang/rust (rust)</summary>

###
[`v1.91.1`](https://redirect.github.com/rust-lang/rust/blob/HEAD/RELEASES.md#Version-1911-2025-11-10)

[Compare
Source](https://redirect.github.com/rust-lang/rust/compare/1.91.0...1.91.1)

\===========================

<a id="1.91.1"></a>

- [Enable file locking support in
illumos](https://redirect.github.com/rust-lang/rust/pull/148322). This
fixes Cargo not locking the build directory on illumos.
- [Fix `wasm_import_module` attribute
cross-crate](https://redirect.github.com/rust-lang/rust/pull/148363).
This fixes linker errors on WASM targets.

</details>

---

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---

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rust-toolchain.toml

@@ -1,4 +1,4 @@
 [toolchain]
-channel = "1.91.0"
+channel = "1.91.1"
 components = ["rustfmt", "clippy"]
 profile = "minimal"