fix: also install proj-bin for skyproj build

skyproj setup.py looks for the proj executable on PATH (or PROJ_DIR).
libproj-dev only provides headers; proj-bin provides the binary.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: cailmdaley

Dockerfile

@@ -38,6 +38,7 @@ RUN apt-get update -y --quiet --fix-missing && \
     openmpi-bin \
     libopenmpi-dev \
     libproj-dev \
+    proj-bin \
     pkg-config \
     protobuf-compiler \
     psfex=3.21.1-1 \