fix(topology): increase connector line stroke width and dash size for better visibility

[MilosPaunovic]

Summary

• Increases edge path stroke-width from 1 to 1.5 in topology.scss for thicker, more visible connector lines
• Updates stroke-dasharray from 1.5 3 to 4 4 in EdgeNode.vue for larger, more readable dashes

Related

Closes https://github.com/kestra-io/kestra-ee/issues/8417.

Test plan

• Open an execution and navigate to the Topology tab
• Verify connector lines between task nodes are clearly visible in both light and dark mode
• Verify error (red) and warning (orange) edge colors still render correctly

[github-actions]

🐋 Docker image

ghcr.io/kestra-io/kestra-pr:16650

docker run --pull=always --rm -it -p 8080:8080 --user=root -v /var/run/docker.sock:/var/run/docker.sock -v /tmp:/tmp ghcr.io/kestra-io/kestra-pr:16650 server local