render: improve image label placement

[gavin-ts]

Summary

Updates logic for image label placement to avoid overlaps with container labels.

Details

• fixes Labels overlapping when image is used #468 spacing between objects with icons and description outside the frame #403 layout: Place labels in dagre/elk below image #126
• adds e2e test
• place image labels on the bottom of shape and pass dagre layout the height including the label
• Note: this is for shape: image specifically, other shapes with an icon attribute will have labels placed inside top center similarly to a container with an image inside

e2e report changes for dagre

[alixander]

TODO TALA

Nah, TALA's label placement is good enough

[alixander]

Note: this is for shape: image specifically, does not apply to other shapes with an icon attribute

why not?

[gavin-ts]

Note: this is for shape: image specifically, does not apply to other shapes with an icon attribute

why not?

the situation with icons is a bit different more similar to a container+image, updated to move these to inside top center instead which should avoid any overlaps with a container label

[alixander]

changelog plz

[alixander]

i think this closes #403 too, can u add to PR description

[alixander]

And this! #126