GH: cache packages

.github/workflows/pytest.yml

@@ -30,9 +30,18 @@ jobs:
       - name: Install uv
         shell: bash
         run: curl -LsSf https://astral.sh/uv/install.sh | sh
+      - name: Cache uv virtualenv
+        id: cache-uv
+        uses: actions/cache@v3
+        with:
+          path: .venv
+          key: uv-venv-${{ runner.os }}-${{ matrix.python-version }}-${{ hashFiles('uv.lock') }}
       - name: Create virtual environment
         shell: bash
-        run: uv venv
+        run: |
+          if [ ! -d ".venv" ]; then
+            uv venv
+          fi
       - name: Install dependencies
         shell: bash
         run: uv pip install -e ".[dev]"