dockerfile: add pyriht as a docker target

Dockerfile

@@ -1,4 +1,5 @@
-FROM python:3.12-slim AS req
+ARG PYTHON=3.12
+FROM python:${PYTHON}-slim AS req
 WORKDIR /app
 RUN set -x && \
   apt-get update && \
@@ -17,6 +18,16 @@ RUN pip install --no-cache-dir -e . && nomadtools --version
 COPY . .
 RUN ./unit_tests.sh
 
+FROM req AS pyright
+RUN pip install pyright && pyright --version
+COPY ./pyproject.toml ./pyproject.toml
+COPY src/ src/
+RUN pyright src/
+COPY ./requirements-test.txt .
+RUN pip install --no-cache-dir -r ./requirements-test.txt
+COPY tests/ tests/
+RUN pyright tests/
+
 FROM req AS app
 COPY ./pyproject.toml ./pyproject.toml
 COPY ./src ./src