feat: expose if view has changed

[flekschas]

This PR exposes isViewChanged in the payload of draw, drawing, and view events

Description

What was changed in this pull request?

• Exposes isViewChanged in the payload of draw, drawing, and view events
• Clean up worker URL after creation

Why is this PR necessary?

To make it easier for consumers to know whether a draw call was triggered by a view change

Checklist

• Provided a concise title as a semantic commit message (e.g. "fix: correctly handle undefined properties")
• CHANGELOG.md updated
• Tests added or updated
• Documentation in README.md added or updated
• Example(s) added or updated
• Screenshot, gif, or video attached for visual changes