feat: render markers as part of djs-visual

[marstamm]

This allows styling with canvas.addMarker and css, as described in our examples.
Requires bpmn-io/diagram-js#906

related to camunda/camunda-modeler#4307

[nikku]

I like this change; local markers (for coloring) seems to be a good thing to do, and it benefits the issue at hand (CSS styling), too.

Still need to E2E test this against a larger diagram. Good job 👏

[marstamm]

I manually tested against complex.bpm (https://demo.bpmn.io/s/application-processing) and there was no noticeable performance decrease

[nikku]

I don't assume that rendering of these cryptic markers was ever done via userland CSS, hence I regard these changes as not breaking.

Good job 🌵

[nikku]

@marstamm Please verify the diagram-js update does not break dmn-js, and if it does bump diagram-js there, too.

Please also cut a release of this change (in bpmn-js), so users can have a clean (and compatible) install again.

[marstamm]

I verified that the diagram-js update does not break dmn-js. I'll release bpmn-js soon, but old bpmn-js versions are also compatible with the new diagram-js version.

Only reason some tests failed before the update was a CSS selector checking for a certain number of paths in a visual, which broke the assertion when we added the marker with an additional path. The behavior was still working as intended

[marstamm]

I want to get #1676 (comment) into the release

[marstamm]

Released as v17.8.0