Fix K8s deployment with init container and proper security context

- Add init container to set up config files with correct ownership
- Run main container as socktop user (UID 100, GID 101) from the start
- Use fsGroup to ensure proper volume permissions
- Add emptyDir volume for /var/lib/socktop to avoid permission issues
- Create docker-entrypoint.sh wrapper to detect root vs non-root execution
  - Root mode: uses init-config.sh for Docker/docker-compose
  - Non-root mode: directly runs entrypoint.sh for K8s
- Update deployment command format to work with new entrypoint

This resolves 'Operation not permitted' errors when running in K8s
with security contexts that restrict user switching and ownership changes.

Dockerfile

@@ -122,8 +122,18 @@ EXPOSE 8082 3001
 HEALTHCHECK --interval=30s --timeout=3s --start-period=5s --retries=3 \
     CMD curl -f http://localhost:8082/ || exit 1
 
-# Set entrypoint (init-config.sh runs as root, copies configs, then switches to socktop user)
-ENTRYPOINT ["/init-config.sh"]
+# Create a wrapper script that detects if running as root or socktop user
+RUN echo '#!/bin/bash\n\
+    if [ "$(id -u)" -eq 0 ]; then\n\
+    # Running as root - use init-config.sh to set up and switch to socktop\n\
+    exec /init-config.sh "$@"\n\
+    else\n\
+    # Running as socktop user - directly execute entrypoint\n\
+    exec /entrypoint.sh "$@"\n\
+    fi' > /docker-entrypoint.sh && chmod +x /docker-entrypoint.sh
+
+# Set entrypoint to the wrapper
+ENTRYPOINT ["/docker-entrypoint.sh"]
 
 # Default command - use restricted shell that only allows socktop commands
-CMD ["/entrypoint.sh", "webterm-server", "--host", "0.0.0.0", "--port", "8082", "--command", "/usr/local/bin/restricted-shell.sh"]
+CMD ["webterm-server", "--host", "0.0.0.0", "--port", "8082", "--command", "/usr/local/bin/restricted-shell.sh"]