Stop propagation of clicks on Markers

[dabreegster]

Related to #155. If you want to be able to click an empty part of the map and distinguish that from clicking an existing Marker, then I think this is necessary. I don't know if this is reasonable default behavior, or if it should be configurable though.

Testing in an external project, https://acteng.github.io/inspectorate_tools/route_check/critical_issues_log (subject to change).
https://github.com/acteng/inspectorate_tools/blob/main/src/routes/route_check/critical_issues_log/%2Bpage.svelte
I can modify an example here to demonstrate the change, if it's helpful

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[dimfeld]

Yeah this makes sense. Clicking on a marker is fundamentally different from a regular map click.

I think where this could become a problem is if you set a click handler on the Map, but don't actually care about marker clicks specifically and so aren't handling them there. Unfortunately Svelte 4 doesn't let you detect if the Marker has an event listener hooked up, but this is possible with Svelte 5 style event handlers since they're just regular props.

That said, I think this change is still the right one to make since it handles the regular case better, and in the case above you can just add click handlers to your markers too.

[dimfeld]

Published in v0.9.0