pytest: enable colored output in CI (#757)

Pass --color=yes to pytest and export FORCE_COLOR=1 / PY_COLORS=1
so pytest and Rich-based test output render ANSI colors in the
GitHub Actions log viewer, making failures easier to read.

Author: potiuk

.github/workflows/pytest.yml

@@ -35,6 +35,8 @@ jobs:
       - name: Run tests
         run: |
           pipx install uv
-          uv run pytest
+          uv run pytest --color=yes
         env:
           GH_TOKEN: ${{ github.token }}
+          FORCE_COLOR: "1"
+          PY_COLORS: "1"