feat(xmss): Add XMSS (#1228)

Author: mikelodder7

.github/workflows/xmss.yml

@@ -0,0 +1,41 @@
+name: xmss
+on:
+  pull_request:
+    paths:
+      - ".github/workflows/xmss.yml"
+      - "xmss/**"
+      - "Cargo.*"
+  push:
+    branches: master
+
+defaults:
+  run:
+    working-directory: xmss
+
+env:
+  CARGO_INCREMENTAL: 0
+  RUSTFLAGS: "-Dwarnings"
+
+# Cancels CI jobs when new commits are pushed to a PR branch
+concurrency:
+  group: ${{ github.workflow }}-${{ github.head_ref || github.run_id }}
+  cancel-in-progress: true
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        rust:
+          - 1.85.0 # MSRV
+          - stable
+    steps:
+      - uses: actions/checkout@v6.0.2
+      - uses: dtolnay/rust-toolchain@master
+        with:
+          toolchain: ${{ matrix.rust }}
+      - run: cargo build --benches
+      - run: cargo build --benches --all-features
+      - run: cargo test --release
+      - run: cargo test --all-features --release
+      - run: cargo test --no-default-features --release