Provide users with a way to ensure elements across artboards are aligned

[patriciafmed]

Summary

Users of Inspiration need a way to align elements across different frames (artboards) within a moodboard.

Currently, alignment tools and guide lines only work within the same frame, making it impossible to ensure that elements placed in different frames share the same position. This creates inconsistencies when designing compositions that span multiple artboards.

Basic example

1. Create two frames (artboards) in a moodboard.
2. Place one element inside each frame.
3. Try to align both elements:
   • Guide lines do not appear across frames.
   • Align tools do not work between elements in different frames.

Result:
There is no reliable way to ensure both elements are aligned in the same position.

Motivation

Users often work with multiple frames as part of a single composition and need to maintain visual consistency between them.

Current limitations:

• Guide lines do not work across frames.
• Align tools are restricted to elements within the same frame.

Expected outcome:

• Provide a mechanism to align elements across frames.
• Ensure consistent positioning between artboards.

A possible approach could be introducing a grid system inside frames (similar to the canvas grid), allowing users to visually align elements across different frames.

[jesusmpc]

Related to #1041