Add very simple CI pipeline

.gitea/workflows/ci.yml

@@ -0,0 +1,37 @@
+name: CI
+
+on:
+  - push
+  - pull_request
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Setup Rust
+        uses: actions-rust-lang/setup-rust-toolchain@v1
+        with:
+          components: clippy,rustfmt
+          cache: true
+
+      - name: Cache cargo registry & build
+        uses: swatinem/rust-cache@v1
+        with:
+          path: |
+            ~/.cargo/registry
+            ~/.cargo/git
+            target
+
+      - name: Build
+        run: cargo build --workspace --all-features --locked
+
+      - name: Run tests
+        run: cargo test --workspace --all-features --locked
+
+      - name: Run clippy
+        run: cargo clippy --all-targets --all-features -- -D warnings
+
+      - name: Check formatting
+        run: cargo fmt --all -- --check