ci: add MSRV (1.80) and beta channel testing

- MSRV job: Ensures we don't accidentally use Rust features newer than 1.80
- Beta job: Early warning for upcoming breakage (allowed to fail)
- Stable remains primary target with full OS matrix

This would have caught today's Rust 1.92 lint regression before it hit stable.

Author: 27Bslash6

.github/workflows/ci.yml

@@ -9,6 +9,26 @@ concurrency:
   cancel-in-progress: true
 
 jobs:
+  # MSRV check - ensures we don't accidentally use newer Rust features
+  test-msrv:
+    name: MSRV (1.80)
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v5
+
+      - name: Install Rust toolchain (MSRV)
+        uses: dtolnay/[email protected]
+
+      - name: Cache cargo registry
+        uses: Swatinem/rust-cache@v2
+
+      - name: Build (all features)
+        run: cargo build --all-features
+
+      - name: Run tests (all features)
+        run: cargo test --all-features
+
+  # Primary test matrix - stable on all platforms
   test:
     runs-on: ${{ matrix.os }}
     strategy:
@@ -40,6 +60,28 @@ jobs:
       - name: Run FFI tests
         run: cargo test --features ffi
 
+  # Beta channel - early warning for upcoming breakage (allowed to fail)
+  test-beta:
+    name: Beta (early warning)
+    runs-on: ubuntu-latest
+    continue-on-error: true
+    steps:
+      - uses: actions/checkout@v5
+
+      - name: Install Rust toolchain (beta)
+        uses: dtolnay/rust-toolchain@beta
+        with:
+          components: clippy
+
+      - name: Cache cargo registry
+        uses: Swatinem/rust-cache@v2
+
+      - name: Run clippy
+        run: cargo clippy --all-features -- -D warnings
+
+      - name: Run tests (all features)
+        run: cargo test --all-features
+
   security:
     runs-on: ubuntu-latest
     steps: