GH-143613: Add colours and some more edges to executor visualization graph

[markshannon]

Example (svg):

https://gist.github.com/markshannon/de7d7f9cee1061689c475d8889d9d62f

• Issue: Add highlighting and colour to the visualisation graph of executors. #143613

[bedevere-bot]

⚠️⚠️⚠️ Buildbot failure ⚠️⚠️⚠️

Hi! The buildbot ARM64 macOS 3.x (tier-2) has failed when building commit 6db952e.

What do you need to do:

1. Don't panic.
2. Check the buildbot page in the devguide if you don't know what the buildbots are or how they work.
3. Go to the page of the buildbot that failed (https://buildbot.python.org/#/builders/725/builds/12547) and take a look at the build logs.
4. Check if the failure is related to this commit (6db952e) or if it is a false positive.
5. If the failure is related to this commit, please, reflect that on the issue and make a new Pull Request with a fix.

You can take a look at the buildbot page here:

https://buildbot.python.org/#/builders/725/builds/12547

Failed tests:

• test_urllib2net

Summary of the results of the build (if available):

==

Click to see traceback logs

remote: Enumerating objects: 7, done. remote: Counting objects: 14% (1/7) remote: Counting objects: 28% (2/7) remote: Counting objects: 42% (3/7) remote: Counting objects: 57% (4/7) remote: Counting objects: 71% (5/7) remote: Counting objects: 85% (6/7) remote: Counting objects: 100% (7/7) remote: Counting objects: 100% (7/7), done. remote: Compressing objects: 25% (1/4) remote: Compressing objects: 50% (2/4) remote: Compressing objects: 75% (3/4) remote: Compressing objects: 100% (4/4) remote: Compressing objects: 100% (4/4), done. remote: Total 4 (delta 3), reused 0 (delta 0), pack-reused 0 (from 0)  From https://github.com/python/cpython * branch main -> FETCH_HEAD Note: switching to '6db952eae9591071eee1ecb279ac6aaa38052f52'. You are in 'detached HEAD' state. You can look around, make experimental changes and commit them, and you can discard any commits you make in this state without impacting any branches by switching back to a branch. If you want to create a new branch to retain commits you create, you may do so (now or later) by using -c with the switch command. Example: git switch -c <new-branch-name> Or undo this operation with: git switch - Turn off this advice by setting config variable advice.detachedHead to false HEAD is now at 6db952eae95 GH-143613: Add colours and some more edges to executor visualization graph (GH-143809) Switched to and reset branch 'main' make: *** [buildbottest] Error 2