feat: Add "Move Up" / "Move Down" menu items to lib unit components

[bradenmacdonald]

This is a workaround for #1994 "Cannot drag a component past a really long component on a unit page" (Since "autoscroll" is disabled in our usage of dnd-kit due to conflicts with our custom collision detection algorithm.)

This implements the workaround proposed in #3110.

I also re-organized the menu to put the destructive remove/delete menu options last, below a divider, for better consistency with course authoring.

Description

Before	After

Testing instructions

Try using both regular drag-and-drop and the new menu items to re-order components in a library unit.

Private ref: MNG-4985

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[bradenmacdonald]

@kdmccormick and/or @navinkarkera could you please review?

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 95.63%. Comparing base (7e7eb0f) to head (3e2c904).
⚠️ Report is 6 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #3111      +/-   ##
==========================================
+ Coverage   95.59%   95.63%   +0.03%     
==========================================
  Files        1403     1402       -1     
  Lines       33239    33222      -17     
  Branches     7780     7782       +2     
==========================================
- Hits        31775    31772       -3     
+ Misses       1415     1403      -12     
+ Partials       49       47       -2     

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[navinkarkera]

@bradenmacdonald Looks good, just found one bug where if you use sidebar menu directly after using the move option once, it uses the old index and breaks the order.

Also, should we use optimistic updates to make the movement instant?

[bradenmacdonald]

Good catch - thanks @navinkarkera. I included those changes.

Also, should we use optimistic updates to make the movement instant?

That would be better, but it seems already pretty fast and this is an "emergency workaround" type situation, so I just want to merge the simplest version for now.

[navinkarkera]

@bradenmacdonald Looks good. Feel free to merge this.

[bradenmacdonald]

Thanks @navinkarkera. @ChrisChV could you please review/approve this so I can merge?

[ChrisChV]

The code looks good! Thanks! 👍

[bradenmacdonald]

Thanks @ChrisChV! Could you please approve the backport as well? #3116