Markdown support

[kamil4]

Fixes https://github.com/LycheeOrg/Lychee/issues/1189

This adds support for markdown in photo and album descriptions.

• I used the marked parser as it was the smallest actively supported one I could find (<50 KB).
• I modified the editing of descriptions to provide a multi-line textarea rather than a single-line input; this required some tweaks as textareas are poorly supported in basicModal and such.
• I added support for displaying album descriptions right under the header. This is enabled by default (though configurable) because I felt that not having it displayed anywhere was an omission in our UI, but I can be persuaded otherwise.
• Much of the work went on the CSS side since we simply didn't support many of the HTML tags that markdown uses in the contexts in which descriptions are displayed. I made sure that basic markdown syntax renders nicely, such as headings/bold/italic/blockquotes/lists/code/rules/links; no guarantees about anything more than that, though it should be easy to extend should the need arise.

There is a corresponding trivial server PR that adds two config variables, one for displaying the album descriptions, the other for enabling markdown.

The PR includes two unrelated fixes:

• The separate view mode was crapping out on opening the sidebar because photo.updateSizeLivePhotoDuringAnimation is not defined in it.
• If the last visited album had an info sidebar open, it would reopen when going to any of the Settings/Logs/Diagnostics/etc. This was because view.photo.hide() was being called unconditionally but it should only be called in photo view.

[sonarcloud[bot]]

SonarCloud Quality Gate failed.   

3 Bugs
0 Vulnerabilities
0 Security Hotspots
1 Code Smell

No Coverage information
1.1% Duplication

[kamil4]

SonarCloud fails because CSS uses font-family: revert to request going back to browser-defaults for backquotes and such; I consider that to be a bug in SonarCloud, not in my code, though I suppose we could request some specific fonts instead...

[nagmat84]

I have merged consistent_json_api into master and rebased your branch markdown-support as markdown-support_rebased onto the new master. To update your PR, I believe the following commands should be the the right ones Attention: I haven't tested them.

Commands:

git checkout master                                                      # Checkout the current master of Lychee-front, the only important thing is that your are not on the branch `markdown-support`
git branch -D markdown-support                                           # Delete your local branch `markdown-support`
git checkout -b markdown-support --track origin/markdown-support_rebased # Checkout a new local branch `markdown-support` from `markdown-support_rebased`
git pull                                                                 # Pull it
git branch -u origin/markdown-support                                    # Change upstream back to `markdown-support`
git push                                                                 # Try to push it, this is expected to fail, but make sure that GIT tries to push to the correct branch
git push --force                                                         # Now push forcefully

[mashb1t]

@kamil4 i assume this feature still is open and waiting for review. I'd also be interested in using at least multiline descriptions, at best markdown support, but i'm not that proficient with JS. Maybe you can take a look again and solve the remaining change requests by @nagmat84. It would be highly appreciated 👍

[ildyria]

Better integration directly in #1303