refactor Dockerfile: adjust NLTK downloader position and update venv path

Dockerfile

@@ -32,7 +32,6 @@ RUN --mount=type=cache,target=/root/.cache/uv \
         uv sync --no-editable; \
     fi
 
-# ← moved here, after venv is built, nltk is guaranteed to exist
 RUN /app/env/.venv/bin/python -m nltk.downloader \
         wordnet omw-1.4 stopwords punkt \
         averaged_perceptron_tagger_eng punkt_tab
@@ -43,12 +42,13 @@ FROM ${BASE_IMAGE}
 
 WORKDIR /app
 
-COPY --from=builder /app/env/.venv /app/.venv
+# venv copied to the SAME path it was built at — shebangs stay valid
+COPY --from=builder /app/env/.venv /app/env/.venv
 COPY --from=builder /app/env /app/env
-# NLTK data sits in /root/nltk_data inside the builder — copy it over too
 COPY --from=builder /root/nltk_data /root/nltk_data
 
-ENV PATH="/app/.venv/bin:$PATH"
+# PATH updated to match
+ENV PATH="/app/env/.venv/bin:$PATH"
 ENV PYTHONPATH="/app/env:$PYTHONPATH"
 
 HEALTHCHECK --interval=30s --timeout=3s --start-period=5s --retries=3 \