Fix darktable docker install

and print version of executable workers on startup

Dockerfile

@@ -66,21 +66,28 @@ RUN go build -v -o photoview .
 
 ### Copy api and ui to production environment ###
 FROM debian:buster
+ARG TARGETPLATFORM
 WORKDIR /app
 
 COPY api/data /app/data
 
-# Use official PPA for Darktable to get the latest version
-RUN echo 'deb http://download.opensuse.org/repositories/graphics:/darktable/Debian_10/ /' | tee /etc/apt/sources.list.d/graphics:darktable.list \
-  curl -fsSL https://download.opensuse.org/repositories/graphics:darktable/Debian_10/Release.key | gpg --dearmor | tee /etc/apt/trusted.gpg.d/graphics_darktable.gpg > /dev/null
-
 RUN apt-get update \
   # Required dependencies
-  && apt-get install -y libdlib19 ffmpeg \
-  # Optional dependencies
-  && apt-get install -y darktable; exit 0 \
-  # Cleanup
-  && apt-get clean && rm -rf /var/lib/apt/lists/*
+  && apt-get install -y curl gpg libdlib19 ffmpeg
+
+# Install Darktable if building for a supported architecture
+RUN if [ "${TARGETPLATFORM}" = "linux/amd64" ] || [ "${TARGETPLATFORM}" = "linux/arm64" ]; then \
+  echo 'deb http://download.opensuse.org/repositories/graphics:/darktable/Debian_10/ /' | tee /etc/apt/sources.list.d/graphics:darktable.list \
+  && curl -fsSL https://download.opensuse.org/repositories/graphics:darktable/Debian_10/Release.key | gpg --dearmor | tee /etc/apt/trusted.gpg.d/graphics_darktable.gpg > /dev/null \
+  && apt-get update \
+  && apt-get install -y darktable; \
+  fi
+
+# Remove build dependencies and cleanup
+RUN apt-get purge -y curl gpg \
+  && apt-get autoremove -y \
+  && apt-get clean \
+  && rm -rf /var/lib/apt/lists/*
 
 COPY --from=ui /app/dist /ui
 COPY --from=api /app/photoview /app/photoview