Improvement: Add vertical offset to the outside-left and outside-right regions, resolves #254.

[prasanna-lmsace]

Added an admin setting under the Blocks section, "Outside regions vertical alignment," to align the outside left and right regions vertically with the page content. This includes empty placeholder divs inside these regions and adjusts the height based on the page content offset to ensure proper content positioning.

[abias]

Hi @prasanna-lmsace ,

many thanks for working on this contribution and sorry that it took us so long to review this PR.

I just rebased it onto latest main and had a look at the code.
I think your solution approach is perfectly fine. I just added a "Review changes" commit with language and comment and settings refinements.

Then, when testing manually, I encountered a glitch:
As #643 has been merged in the meantime, I saw that the code adds too much space above the outside-left and outside-right regions on smaller viewports.

On larger viewports, it looked like this (which is perfect):

And on smaller viewports it looked like this:

My gut feeling was that the JS code should be changed in a way that the vertical alignment is only processed on larger viewports. On smaller viewports, it should not do anything. And when resizing from a larger to a smaller viewport, it should revert the vertical alignment and let Bootstrap do its job.

I just went ahead and added this detail to make the PR mergeable.
I will merge it as soon as the tests are green.

Cheers,
Alex