fix: use cdylib-capable Rust for musl builds

Keep Rust 1.85 as the source MSRV, but pin Rust 1.97.1 for the two musl release artifacts because the 1.85 musl targets cannot emit cdylibs.

Author: shps951023

.github/workflows/ci.yml

@@ -74,7 +74,7 @@ jobs:
     runs-on: ${{ matrix.runner }}
     steps:
       - uses: actions/checkout@v4
-      - uses: dtolnay/rust-toolchain@1.85.0
+      - uses: dtolnay/rust-toolchain@1.97.1
         with:
           targets: ${{ matrix.rid == 'linux-musl-x64' && 'x86_64-unknown-linux-musl' || 'aarch64-unknown-linux-musl' }}
       - uses: actions/setup-dotnet@v4

.github/workflows/release.yml

@@ -49,40 +49,49 @@ jobs:
           - runner: windows-latest
             rid: win-x64
             target: x86_64-pc-windows-msvc
+            rust: 1.85.0
             zig: false
           - runner: windows-11-arm
             rid: win-arm64
             target: aarch64-pc-windows-msvc
+            rust: 1.85.0
             zig: false
           - runner: ubuntu-latest
             rid: linux-x64
             target: x86_64-unknown-linux-gnu
+            rust: 1.85.0
             zig: false
           - runner: ubuntu-24.04-arm
             rid: linux-arm64
             target: aarch64-unknown-linux-gnu
+            rust: 1.85.0
             zig: false
           - runner: ubuntu-latest
             rid: linux-musl-x64
             target: x86_64-unknown-linux-musl
+            rust: 1.97.1
             zig: true
           - runner: ubuntu-24.04-arm
             rid: linux-musl-arm64
             target: aarch64-unknown-linux-musl
+            rust: 1.97.1
             zig: true
           - runner: macos-15-intel
             rid: osx-x64
             target: x86_64-apple-darwin
+            rust: 1.85.0
             zig: false
           - runner: macos-latest
             rid: osx-arm64
             target: aarch64-apple-darwin
+            rust: 1.85.0
             zig: false
     runs-on: ${{ matrix.runner }}
     steps:
       - uses: actions/checkout@v4
-      - uses: dtolnay/rust-toolchain@1.85.0
+      - uses: dtolnay/rust-toolchain@master
         with:
+          toolchain: ${{ matrix.rust }}
           targets: ${{ matrix.target }}
       - uses: mlugg/setup-zig@v2
         if: matrix.zig

README.md

@@ -47,6 +47,10 @@ library under `runtimes/{rid}/native/`. .NET selects the matching asset at publi
 
 Rust 1.85 and .NET SDK 8 or later are required.
 
+Rust 1.85 is the source MSRV and builds the Windows, GNU Linux, and macOS libraries. The
+official Rust 1.85 musl targets cannot emit `cdylib` artifacts, so release automation pins
+Rust 1.97.1 for the two musl libraries.
+
 ```powershell
 cargo test --workspace --all-targets --locked
 dotnet build ./src/MiniExcelRust/MiniExcelRust.csproj -c Release