Style MediaWiki internal link based on last revision date of a page

I have a large wiki with a lot of pages, many of which are stale. I want to apply custom CSS to each link based on the age of the page it links to.

I have been digging into the source code of MediaWiki, and for each link, I can get the DBKey starting from a LinkTarget. See the source code here.

I am looking for a process which is essentially:

$dbKey = $target->getDBkey();
$page = find_page_by_title($dbKey);
$last_revision = get_last_revision($page);
// Additional processing based on the date of $last_revision

Alternatively, if there is a way to fetch this information from the API, I could add a JS snippet to recolor the links.

Could anyone point me at resources I could look at to do this?

You could use the HtmlPageLinkRendererEnd hook

https://www.mediawiki.org/wiki/Manual:Hooks/HtmlPageLinkRendererEnd

Just add something like this to your LocalSettings.php

    $wgHooks['HtmlPageLinkRendererEnd'][] = function($linkRenderer, $target, $isKnown, &$text, &$attribs, &$ret) {

        $title = Title::newFromLinkTarget($target);
        $id = $title->getLatestRevID();
        $revStore = MediaWikiServices::getInstance()->getRevisionStore();
        $date = $revStore->getTimestampFromId( $id );

        if ($date > '20230704142055') {
            $attribs['class'] = "old-page";
        }

        if ($date > '20230704142070') {
            $attribs['class'] = "newer-page";
        }        
    
    };

just change the '20230704142055' with your desired or current date

You probably need to add this to the top of your php file also

use MediaWiki\MediaWikiServices;
use Title;