Tidy up Web Modeler docs

[christian-konrad]

There are a few outdated pages and sections in the Web Modeler docs. Following, they are listed to be cleaned up (either removed or adjusted) in this issue.

• https://docs.camunda.io/docs/next/components/modeler/web-modeler/new-web-modeler/ is probably no longer needed (who should have been migrated will have been migrated months ago)
• Screenshots on https://docs.camunda.io/docs/next/components/modeler/web-modeler/launch-cloud-modeler/ are disparate; while it shows a flow of creating a process model from a template, the last screenshot shows a blank model.
• Most of the screenshots in the Web Modeler docs are hard to read, since they have been recorded with a viewport too large. A smaller viewport for the screenshots avoids excessive white-space in the screenshot and puts on-screenshot text into a readable size
• This is a better example for screenshot size: https://docs.camunda.io/docs/next/components/modeler/web-modeler/fix-problems-in-your-diagram/
• The screenshots are missing borders/outlines, thus sometimes they are hard to distinguish from the doc page background (white on white)
• We could use screencasts (GIFs) instead of many consecutive screenshots, if the GIFs help to understand navigation and interaction (Discouraged, see Amara's comment)
• The explanation of the canvas navigation tools in https://docs.camunda.io/docs/next/components/modeler/web-modeler/model-your-first-diagram/ is too verbose and redundant (the "caption" just repeats what's on the tooltips). One screenshot + explanation of the action symbols floating in-text is sufficient and easier to read

[akeller]

We could use screencasts (GIFs) instead of many consecutive screenshots, if the GIFs help to understand navigation and interaction

I'm actively discouraging the use of GIFs or any motion graphics in the docs as we work to define accessibility standards. Please focus on high-quality text descriptions and reducing the number of images in the docs. I'll get more information available internally on the ask-documentation channel after my synchronous review of the Docs Vision 2.0.