feat(ci): add GitHub Actions matrix testing for Node/Rust versions

.github/workflows/matrix.yml

@@ -0,0 +1,57 @@
+name: Matrix Tests
+
+on:
+  push:
+    branches: [main, develop]
+  pull_request:
+    branches: [main, develop]
+
+env:
+  CARGO_TERM_COLOR: always
+
+# Supported versions matrix
+# Rust: 1.75 (MSRV), stable, beta
+# Node: 20 (LTS), 22 (current LTS)
+
+jobs:
+  rust-matrix:
+    name: Contracts (Rust ${{ matrix.rust }})
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        rust: ["1.75", "stable", "beta"]
+    steps:
+      - uses: actions/checkout@v4
+      - uses: dtolnay/rust-toolchain@master
+        with:
+          toolchain: ${{ matrix.rust }}
+          targets: wasm32-unknown-unknown
+      - uses: Swatinem/rust-cache@v2
+        with:
+          key: rust-${{ matrix.rust }}
+      - name: Build contracts
+        run: cargo build --release --target wasm32-unknown-unknown
+      - name: Test contracts
+        run: cargo test --all --features testutils
+
+  node-matrix:
+    name: Frontend (Node ${{ matrix.node }})
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        node: ["20", "22"]
+    defaults:
+      run:
+        working-directory: frontend
+    steps:
+      - uses: actions/checkout@v4
+      - uses: actions/setup-node@v4
+        with:
+          node-version: ${{ matrix.node }}
+          cache: npm
+          cache-dependency-path: frontend/package-lock.json
+      - run: npm ci
+      - run: npm run type-check
+      - run: npm run build

README.md

@@ -107,6 +107,15 @@ Decentralized governance is critical for DAOs, protocols, and communities to mak
 - Stellar CLI (optional, for deployment)
 - Docker & Docker Compose (optional)
 
+### Supported Versions
+
+| Component | Supported versions | Notes |
+|-----------|-------------------|-------|
+| Rust | 1.75 (MSRV), stable, beta | Tested via CI matrix |
+| Node.js | 20 (LTS), 22 (current LTS) | For frontend build |
+
+Matrix build status is tracked in the [Matrix Tests workflow](.github/workflows/matrix.yml).
+
 ### Installation & Testing
 
 ```bash