update: fix docker shutdown issues

Dockerfile

@@ -12,11 +12,12 @@ ENV PYTHONDONTWRITEBYTECODE=1 \
     GIT_BRANCH=${GIT_BRANCH} \
     BUILD_SOURCE=${BUILD_SOURCE}
 
-# Install system dependencies including PostgreSQL client libraries
+# Install system dependencies including PostgreSQL client libraries and tini
 RUN apt-get update && apt-get install -y \
     curl \
     libpq-dev \
     gcc \
+    tini \
     && rm -rf /var/lib/apt/lists/*
 
 # Create app user and directory
@@ -67,5 +68,8 @@ HEALTHCHECK --interval=30s --timeout=10s --start-period=5s --retries=3 \
 # Expose port
 EXPOSE 8080
 
+# Use tini as init process to handle signals and zombie processes properly
+ENTRYPOINT ["tini", "--"]
+
 # Run the application with plugin deployment
 CMD ["/app/deploy-plugin.sh"]