Design view: moveable "new comment" pin

What does this MR do?

This MR is part 2/3 towards #34353 (closed).

It adds the ability to click-and-drag to move the pin for a new comment in Design Management.

The ability to move existing pins will come in future MR's

Screenshots

The video demonstrates:

• Moving the note around
• Attempting to move the note outside of the overlay
• Attempting to move the note, while zoomed in, over the zooming buttons
• Adding the comment after note moved

Demo video

Does this MR meet the acceptance criteria?

Conformity

• Changelog entry
• Documentation (if required)
• Code review guidelines
• Merge request performance guidelines
• Style guides
• Database guides
• Separation of EE specific content

Availability and Testing

• Review and add/update tests for this feature/bug. Consider all test levels. See the Test Planning Process.
• Tested in all supported browsers
• Informed Infrastructure department of a default or new setting change, if applicable per definition of done

Security

If this MR contains changes to processing or storing of credentials or tokens, authorization and authentication methods and other items described in the security review guidelines:

• Label as security and @ mention @gitlab-com/gl-security/appsec
• The MR includes necessary changes to maintain consistency between UI, API, email, or other methods
• Security reports checked/validated by a reviewer from the AppSec team