Add ADR 0040 - Display front cover for books in Preview Panel

[damgam0288]

This PR is related to issue 10120. Following the comment discussion, we decided where to place the front cover for book citations in the UI, and this decision is documented in an ADR. The goal of this PR is to merge this ADR.

The ADR includes details on the proposed UI changes; the screenshots were not duplicated here to avoid redundancy and because they have not been implemented yet.

Mandatory checks

• I own the copyright of the code submitted and I licence it under the MIT license
• Change in CHANGELOG.md described in a way that is understandable for the average user (if change is visible to the user)
• Tests created for changes (if applicable)
• Manually tested changed features in running JabRef (always required)
• Screenshots added in PR description (for UI changes)
• Checked developer's documentation: Is the information available and up to date? If not, I outlined it in this pull request.
• Checked documentation: Is the information available and up to date? If not, I created an issue at https://github.com/JabRef/user-documentation/issues or, even better, I submitted a pull request to the documentation repository.

[koppor]

First comments on the "syntax", before I concentrate on the comments.

[koppor]

Please store the image in the repository, too.

Name it 0040-placement-sidepane.png. Do it for the others accordingly. (if it is jpg, use jpg as file extension)

[damgam0288]

Should I put it in the docs/decisions folder?

[koppor]

Yes. With the filename prefix 0040-*, it will sorted next to the ADR.

[koppor]

@damgam0288 I am still waiting for the images.

[damgam0288]

Have uploaded them now

[koppor]

@damgam0288 You also need to change all image links. That means, instead of github.com ..., the respective file should be referenced.

[damgam0288]

sorry! I missed that. Have updated now.

[koppor]

Omit numbers in the headings. Remove them.

[koppor]

Remove 3.

[koppor]

Place the image before this list. Also for the other images.

[calixtus]

I would not include a one-time configurable preference option here. Only if the default behaviour is a major problem. In that case, we should change the default behaviour.

[koppor]

The "bad" describes "only" the case if users do not have the entry preview opened.

Suggested change

	* Bad, because users will have to click multiple times (enable preview tab, open entry editor) to see the book cover.
	* Bad, because coupled to the preview, which is coupled to the entry editor: In case the entry editor is closed, users will have to open the entry editor and navigate to the tab "Preview" or "Requried fields".

I think @damgam0288 did not see that the entry preview is embedded in the tab "Required fields"

[koppor]

I renamed ADR-0040 in the main branch to ADR-0041 to ease merging (otherwise, we would need to rename all files here)