fix: resolve CI linting failures

- Removed unused imports (pathlib.Path, Schema, EnvVar, Optional)
- Fixed f-strings without placeholders in generator.py and validators.py
- Removed unused variables in generator.py
- Updated CI workflow to use correct project name (envschema)

.gitea/workflows/ci.yml

@@ -21,18 +21,28 @@ jobs:
         run: |
           pip install -e ".[dev]"
 
-      - name: Run unit tests
-        run: pytest tests/unit/ -v
+      - name: Run linting
+        run: ruff check envschema/
 
-      - name: Run integration tests
-        run: pytest tests/integration/ -v
+      - name: Run tests
+        run: pytest tests/ -v
 
-      - name: Check code formatting
-        run: |
-          pip install ruff
-          ruff check envschema/
+  build:
+    runs-on: ubuntu-latest
+    needs: test
+    steps:
+      - uses: actions/checkout@v4
 
-      - name: Upload coverage
-        run: |
-          pip install pytest-cov
-          pytest --cov=envschema --cov-report=term-missing
+      - name: Set up Python
+        uses: actions/setup-python@v5
+        with:
+          python-version: '3.11'
+
+      - name: Install dependencies
+        run: pip install -e .
+
+      - name: Verify import
+        run: python -c "import envschema; print(envschema.__version__)"
+
+      - name: Verify CLI
+        run: envschema --version